Whip Scorpions and Camel Spiders from the Early Cretaceous Crato Formation of Brazil.

Whip Scorpions, Uropygi, are a highly distinctive group of Arachnids with large claws, robust, heavily sclerotized bodies and a long whip-like, post-abdominal flagellum, as well as the ability to squirt an offensive, vinegar-like liquid as a defence mechanism. There are about 126 extant species of Whip Scorpions, as well as eleven described fossil species, with the oldest coming from the Carboniferous. 

Camel Spiders, Solifugae, are large, Spider-like Arachnids, lacking the ability to produce silk, and having extremely enlarged chelicerae (fangs) and leg-like pedipalps which are held above the ground when moving. There are about 1209 extant species of Camel Spider, but only six known fossil species, the oldest of which again comes from the Carboniferous.

The Crato Formation outcrops on the northern flanks of the Chapada do Araripe, a plateau on the border between Ceará, Pernambuco andPiauí States in northern Brazil. In is noted for its exceptionally well-preserved fossils, which include Dinosaurs, Crocodiles, Fish, Pterosaurs, Crustaceans, Arachnids, Plants and most notably Insects, which are present in large numbers, often showing exceptional preservation. These Insects are of particular interest as they date from a time in the Early Cretaceous when Flowering Plants were rapidly diversifying, and relationships between Insect and Plant groups that would come to dominate the Earth’s terrestrial biology were being formed.

In a paper published in the journal PeerJ on 3 January 2024, William Santana, Allysson Pinheiro, Thiago Andrade Silva and Daniel Lima of the Museu de Paleontologia Plácido Cidade Nuvens at the Universidade Regional do Cariri describe a new species of Whip Scorpion from the Crato Formation, as well as a new specimen of the Crato Camel Spider Cratosolpuga wunderlichi.

The new Whip Scorpion species is placed in the genus Mesoproctus, and given the specific name rayoli in honour of Rafael Ribeiro Rayol a Brazilian federal attorney, who helped, along with the Brazilian Federal Police, helped recover a significant amount of fossil material from the Crato which was being smuggled out of the country (an ongoing problem for Brazilian palaeontology), including the specimens from which the species is described, as part of 'Operation Santana Raptor'.

Mesoproctus rayoli Holotype MPSC A4295. Ventral view. Scale bar is 30 mm. Santana et al. (2024).

Mesoproctus rayoli is described from two specimens, both recovered by Operation Santana Raptor the first of which is complete an measures 65.9 mm in length, while the second is incomplete, preserving only the forepart of the body. A third specimen in the collection of the Museum für Naturkunde Berlin, is also assigned to the species. This specimen was described as Mesoproctus sp. in 2002 in a paper by Jason Dunlop of the Museum für Naturkunde Berlin and David Martill of the University of Portsmouth, who collected the specimen legally in the 1990s. 

Mesoproctus rayoli Paratype MPSC A4205. Dorsal view. Scale bar is 10 mm. Santana et al. (2024).

The genus Mesoproctus was first designated by Jason Dunlop in 1998 to describe Mesoproctus rowlandi, from a single Crato specimen held in the collection of the Ulster Museum. The specimen described by Dunlop and Martill as Mesoproctus sp was substantially larger than the only known specimen of Mesoproctus rowlandiI, and neither were very well preserved, making it impossible for Dunlop and Martill to be sure that this was not an older specimen of the same species. The better preservation of Santana et al.'s specimens enables them to be confident that they do have a separate specimen, and that the Museum für Naturkunde Berlin specimen belongs to this.

Santana et al. also describe a new specimen of Cratosolpuga wunderlichi, a Camel Spider first described in 1996 by Paul Seldon, then of the University of Manchester and William Shear of Hampden-Sydney College, to describe a specimen from the Crato held by a private collector in Germany. Several other specimens of this species have subsequently been described, however, Santana et al.'s specimen shows several features which have not been seen before, including a styliform flagellum with a bulbous base on the chelicera, a structure present only in adult males. The specimen was collected at Santana do Cariri in Ceará State, Brazil, and donated to the Museu de Paleontologia Plácido Cidade Nuvens via the Projeto Força Tarefa, which encourages local children to collect and contribute fossils to the museum.

Cratosolpuga wunderlichi MPSC A6696. Dorsal view. Scale bar is 10 mm. Santana et al. (2024).

The new Arachnid specimens described by Sanatana et al. provide further insight into the nature of the Early Cretaceous Crato environment. They note that Whip Scorpions and Camel Spiders both favour arid environments, as do a number of other Arthropods and Plants found in these deposits. The theory that the Crato may have been arid is further supported by the presence of salt pseudomorphs and gypsum beds, which tend to form around hypersaline bodies of water in arid environments.

The study also emphasises the importance of both good law enforcement and community engagement programs in preserving the geological and palaeontological heritage of Brazil, and keeping material from important deposits such as Crato within the country, where they can be studied by local scientists and interpreted within the context of the environment where they were found.

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Collection of Bronze Age axes discovered in Pomerania, Poland.

Archaeologists in the Starogard Forest District of Pomerania, northern Poland, have recovered a collection of five Bronze Age Axes, which were found by an amateur metal detectorist. Denis Konkol, a history enthusiast, was detecting with official permission (required by law in Poland) when he made the discovery, and informed the local authorities. 

Five Bronze Age axes discovered in the Starogard Forest, Poland. Nadleśnictwo Starogard.

The axes are of a type known as tautušiai, which are large axe-heads with a slender handle with elevated edges and a broad blade, which were made in eastern Poland and Lithuania between about 1700 and about 1300 BC. Small groups of these axes are thought to have been buried together for religious reasons, although this is the first such collection uncovered in Poland for about 20 years. More common from the same period, are small amounts of jewelery, also ritually buried.

One of the five tautušiai axes uncovered in Pomerania. Nadleśnictwo Starogard.

The axes will be taken to the Archaeological Museum in Gdańsk for study and preservation. 

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Asteroid 2023 CX1 falls to Earth over the English Channel.

Slightly before 9.20 pm local time (8.20 pm GMT) on Sunday 12 February 2023, Hungarian astronomer Krisztián Sárneczky of the Konkoly Observatory observed a Near Earth Object moving rapidly across the northern sky. He recorded this as SAR2667, and reported the finding to the International Astronomical Union's Minor Planet Centre, where the sighting was confirmed, and given the provisional designation 2023 CX1, which implies that it was the 48th asteroid (object X1 - in numbering asteroids the letters A-Z, excluding I, are assigned numbers from 1 to 25, with a number added to the end each time the alphabet is ended so that A = 1, A1 = 26, A2 = 51, etc., which means that X1 = 25 + 23 = 48) discovered in the first half of February 2023 (period 2023 C - the year being split into 24 half-months represented by the letters A-Y, with I being excluded). Later that evening the European Space Agency announced that it's scientists had calculated the asteroid was likely to impact the Earth the following day, somewhere around the French city of Rouen. 

Image of 2023 CX1 captured by the Osservatorio Astronomico Sormano in Italy slightly before midnight local time (slightly before 11.00 pm GMT) on Sunday 12 February 2023. This was one of the observations which enabled the European Space Agency to track the path of the asteroid, which was only the seventh asteroid detected before impacting the Earth, and predict the area in which it was likely to fall. Osservatorio Astronomico Sormano.

Slightly before 3.00 am GMT on Monday 13 February, witnesses across southern England and Wales, northern France, most of Belgium, the southern part of the Netherlands and western Germany reported seeing a bright fireball over the English Channel, disappearing somewhere to the north of Dieppe. A fireball is defined as a meteor (shooting star) brighter than the planet Venus. These are typically caused by pieces of rock burning up in the atmosphere, but can be the result of man-made space-junk burning up on re-entry, although on this occasion the object was confirmed to be the newly discovered asteroid, 2023 CX1.

A fireball meteor caused by asteroid 2023 CX1 entering the Earth's atmosphere over the English Channel, observed from the southern Netherlands. Gijs de Reijke.

Objects of this size probably enter the Earth's atmosphere several times a year, though unless they do so over populated areas they are unlikely to be noticed. They are officially described as fireballs if they produce a light brighter than the planet Venus. The brightness of a meteor is caused by friction with the Earth's atmosphere, which is typically far greater than that caused by simple falling, due to the initial trajectory of the object. Such objects typically eventually explode in an airburst called by the friction, causing them to vanish as an luminous object. However, this is not the end of the story as such explosions result in the production of a number of smaller objects, which fall to the ground under the influence of gravity (which does not cause the luminescence associated with friction-induced heating).

Heat map showing areas where sightings of the meteor were reported (warmer colours indicate more sightings), and the apparent path of the object (blue arrow). American Meteor Society.

These 'dark objects' do not continue along the path of the original bolide, but neither do they fall directly to the ground, but rather follow a course determined by the atmospheric currents (winds) through which the objects pass. Scientists are able to calculate potential trajectories for hypothetical dark objects derived from meteors using data from weather monitoring services.

The calculated trajectory of 2023 CX1 as it fell to Earth. Simon Anghel/Institut de mécanique céleste et de calcul des éphémérides/Observatoire de Paris. 

Asteroid 2023 CX1 is calculated to have been about 233 000 km from the Earth (i.e. about 61% of the distance to the Moon) when it was discovered, and to previously have had a 799 day (2.19 year) orbital period, with an elliptical orbit tilted at an angle of 3.56° to the plain of the Solar System which took in to 0.92 AU from the Sun (92% of the distance at which the Earth orbits the Sun) and out to 2.45 AU (245% of the distance at which the Earth orbits the Sun, and more than the distance at which the planet Mars orbits the Sun). It would therefore have been classed as an Apollo Group Asteroid (an asteroid that is on average further from the Sun than the Earth, but which does get closer). This means that Asteroid 2023 CX1 had occasional close encounters with the Earth, with the last having happened in June 2000.

The former orbit of asteroid 2023 CX1. JPL Small Body Database.

Asteroid 2023 CX1 is thought to have had a diameter of about a metre, and to have exploded in an airburst in diameter), and an object of this size would be expected to explode in an airburst (an explosion caused by superheating from friction with the Earth's atmosphere, which is greater than that caused by simply falling, due to the orbital momentum of the asteroid) more than 40 km above the English Channel. Nevertheless, it was calculated that the asteroid could potentially have scattered fragments on the coast of Normandy between Dieppe and Doudeville, with the potential to have produced pieces as large as 2 kg. A search was organised by the Fireball Recovery and Interplanetary Observation Network involving many volunteers and researchers, who assembled on Wednesday 15 February to scour this area. This led to the discovery of a single fragment in a field close to the town of Saint-Pierre-le-Viger, by student Loïs Leblanc. 

The single known surviving fragment of asteroid 2023 CX1, a piece of black rock weighing about 100g, found in a field near the town of Saint-Pierre-le-Viger, by student Loïs Leblanc on 15 February 2023. Fireball Recovery and Interplanetary Observation Network.

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Ameronothrus retweet: A second species of Japanese Marine-associated Oribatid Mite discovered on Twitter.

Most Arachnids are associated with terrestrial or freshwater ecosystems (Sea Spiders, Pycnogonida, and Horseshoe Crabs, Xiphosura, are generally viewed as Chelicerate Arthropods closely related to, but outside the Arachnida), although some species have colonised inter-tidal zones, notably the Marine Spider, Desis marina, of New Zealand, and a variety of Oribatid Mites from the Superfamily Ameronothriodae. 

Four separate families of Ameronothriod Mites are considered to have colonised the inter-tidal zones, the Fortuyniidae and Selenoribatidae, which are found in tropical and subtropical zones, the Podacaridae, found in the southern temperate and polar zones, and the Ameronothridae, found in northern temperate and polar zones, although some experts consider the Ameronothridae and Podacaridae should be treated as a single family.

The Ameronothridae as it is currently defined comprises a single genus, Ameronothrus, which currently contains 14 valid species, the most recently identified of which Ameronothrus twitter, was described in 2021 after pictures of an unknown Mite from the inter-tidal zone of the Chiba Peninsula on Honshu Island, Japan, were posted on the social media platform Twitter.

In a paper published in the International Journal of Aracology on 19 May 2022, Tobias Pfingstl of the Department for Biodiversity and Evolution at the University of Graz, Shimpei Hiruta of the Center for Molecular Biodiversity Research at the National Museum of Nature and Science, Iris Bardel-Kahr, also of the Department for Biodiversity and Evolution at the University of Graz, Yuito Obae of the Graduate School of Sustainability Science at Tottori University, and Satoshi Shimano of the Science Research Center at Hosei University, describe a new species of Ameronothrus discovered as a result of the discovery of Ameronothrus twitter being discussed on the social media platform after which it was named.

The new species is named Ameronothrus retweet, due to the way in which it was discovered, on the basis of photographs posted in response to a tweet (Twitter post) announcing the discovery of Ameronothrus twitter. The photographs were taken by Yuito Obae of of some mites he discovered on Iwado Rock Beach on the Japan Sea (north) coast of Honshu, which he thought might be another population of Ameronothrus twitter, but were subsequently recognised as another new species.

Specimens of Ameronothrus retweet range from 641 to 859 µm in length, and are dark brown or black in colour, with a densely granulated cuticle, the granules being larger on the lateral sides of the body. As with other Ameronothriod Mites, Ameronothrus retweet appears to feed on Algae, Fungi, or Lichen found in the inter-tidal zone.

Photographs of male (upper row) and female (lower row) Ameronothrus retweet specimens in dorsal (left side) and ventral view (right side). Pfingstl et al. (2022).

Unusually for an Oribatid Mite, Ameronothrus retweet shows sexual dimorphism, with the females showing strongly folded gastronotic integument and considerably shorter epimeral, genital, and aggenital setae than seen in the males. While sexual dimorphism has not previously been recorded in an Ameronothriod Mite, it has been recorded in a number of other Oribatid Mite species associated with aquatic or intermittently wet environments, so the presence of such a trait in a species of Ameronothrus should not be seen as a complete surprise. The purpose of sexual dimorphism in Oribatid Mites found in aquatic environments remains unknown, although increasing the number of species in which this is known may help to solve this mystery.

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Acropora cervicornis: Assessing the success of Staghorn Coral restoration in the southeast Dominican Republic.

Comprised of 368 species, the genus Acropora is the world’s most abundant coral group. Of these species, only Acropora cervicornis, Acropora palmata, and the hybrid Acropora prolifera are found in the Caribbean and Western Atlantic. Historically, Acropora cervicornis and Acropora palmata have dominated the region, building shallow reefs with branched structures that provide crucial habitats for reef organisms. The interactions and complex flows of energy around these species lead to high levels of primary productivity and interspecies interactions. The early 1980s saw a loss of up to 97% of both Acropora cervicornis and Acropora palmata cover caused by several factors: White Band Disease, hurricanes and storms, corallivorous predation, thermal stress, pollution, and, in the case of A. palmata, mean sea level increase. To this day, these issues continue to prevail with no significant signs of recovery Both species have been listed as Critically Endangered by the International Union for Conservation of Nature and included in Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora. Proposed recovery efforts for this genus at regional and local levels have included the implementation of Marine Protected Areas, Coral restoration, and the control of Coral-degrading terrestrial sources of pollution. Pioneering work on coral restoration began in the 1970s and 1980s in the Indo-Pacific Ocean and Red Sea. In the 1990s, these same areas saw the first large-scale restoration projects, and a Coral gardening technique was soon implemented. In the initial phase, Coral are grown at an in situ nursery and are outplanted in the second phase. Coral gardening has higher success rates than direct transplanting because it avoids mechanical damage, predation, and competition for space with nurseries during propagation. Acropora Coral gardening restoration started in the 1990s and 2000s in Puerto Rico.However, few published studies have focused on the long-term success of restoration projects since it is difficult to assess the performance of propagation efforts.

In a paper published in the journal PeerJ on 17 April 2020, Johanna Calle-Triviño of the Departamento de Recursos del Mar at the Unidad Mérida, and Wave of Change Iberostar Hotels & Resorts, Renata Rivera-Madrid of the Unidad de Bioquímica y Biología Molecular de Plantas at the Centro de Investigación Científica de Yucatán, María Geovana León-Pech of the Department of Biological Science at the University of Rhode Island, Camilo Cortés-Useche, also of the Departamento de Recursos del Mar at the Unidad Mérida, Rita Inés Sellares-Blasco of the Fundación Dominicana de Estudios Marinos, Margarita Aguilar-Espinosa, also of the Unidad de Bioquímica y Biología Molecular de Plantas at the Centro de Investigación Científica de Yucatán, and Jesús Ernesto Arias-González, again of the Departamento de Recursos del Mar at the Unidad Mérida, report on the success of an Acropora restoration program on the southeast coast of the  Dominican Republic.

In the Dominican Republic, Acropora cervicornis is disappearing from areas where it was once common. In 2011, the Fundación Dominicana de Estudios Marinos created the Coral Restoration Program in Bayahibe which is located on the southeastern part of the island. Initially, the restoration program worked with Acropora cervicornis fragments from one of the Punta Cana Ecological Foundation nurseries and fragments rescued from the Bayahibe area. Later, the first nursery was expanded and new nurseries were created to take advantage of the species’ fast growth and high survival rate.

Calle-Triviño et al.'s study offers a temporal assessment of the Coral restoration program since its implementation in 2011–2017, in addition to a preliminary analysis of the strong cyclonic seasons that struck the Greater Caribbean region in 2016 and 2017.

The two main objectives of this study were: (1) to assess the coral restoration program over time, analyzing the results within the context of the 'regional restoration benchmarks for Acropora cervicornis'; and (2) to determine the genetic diversity of Acropora cervicornis colonies in the 'main nursery' for use in future regional restoration efforts.

Calle-Triviño et al. conducted the study in eight coral nurseries and six outplanting areas in the Santuario Marino Arrecifes del Sureste located in the Dominican Republic’s Bayahibe Municipality along the southeastern Caribbean coast. This area was declared a Marine Protected Area by Decree 571-09 on August 7, 2009. This Marine Protected Area attracts 2000–2500 tourists daily, with an annual average of 600 000 visitors and generating a US$250 million in revenue. Tourism’s impact on coastal marine ecosystems is significant, mainly due to local stress factors such as the constant flow of boats and visitors, snorkeling activities, water sports, and 'artisanal' fishing.

Study area in Bayahibe coast, Dominican Republic. Nurseries: FUNDEMAR-N1 (the 'mother nursery'), Catalonia-N2, Dreams-N3, Scuba fun-N4, Viva-N5, Catalina-N6, Iberostar-N7, Canoa-N8. Outplanting reefs: FUNDEMAR-T1, Coralina-T2, Pepito I-T3, Pepito II-T4, Atlantic Princess-T5, Costa Romántica-T6. Calle-Triviño et al. (2020).

The pilot project began in 2011 with one nursery, the 'main nursery', comprised of four structures, each supporting approximately 30 fragments. Most of the Acropora cervicornis fragments came from one of the Punta Cana Ecological Foundation’s nurseries (with multiple genotypes collected in Punta Rusia, Samaná, Bávaro, Punta Cana, and La Caleta National Submarine Park), while other fragments were collected from the Bayahibe region. Since its beginning, the restoration program’s design involved the local community, and included local volunteers such as fishermen, boat captains, tourism service providers, park rangers, diving instructors, divers, university students, and hotel owners. All received comprehensive training and contributed their time, equipment, materials, and boats at different developmental stages of the restoration program.

In 2012, the main nursery was expanded using 2nd and 3rd generation corals propagated within the nursery (FUNDEMAR-N1). Twenty-two structures, holding over 600 fragments, were added. Seven frames were built with welded electromesh measuring 1.30 m long and 2 m wide, eight domes, a table build with metal corrugated rod approximately 1 m high, and six ropes 5.5 m high and 2 m wide. This nursery was the prototype for the remaining seven nurseries and six outplanted areas that were in use until 2017.

Structures used in the Bayahibe nurseries. (A) Table type structure, capacity for 50 fragments (B) Frame type structure, capacity for 30 fragments (C) Dome type structure, capacity for 20 fragments (D) Rope type structure, capacity for 30 fragments. Calle-Triviño et al. (2020).

Subsequent dives were initiated to select outplanted sites, which were chosen based on the following criteria: depth, presence of wild Acropora colonies, low sedimentation, low Macroalga cover, and the presence of Calcareous Coral Algae. Before outplanting, the substrate was cleaned using different hand tools (brushes, chisels, hammers) to remove Algal mats, sediments, or Macroalgae, but the Calcareous Coral Algae was left alone. Once the substrate was prepared, steel nails were driven directly into the substrate, leaving an approximate distance of 0.5–1 m between the nails. Plastic straps were used to attach the Coral colonies as tightly as possible to the nails to prevent ocean currents from causing friction or loosening the nails. Over time, Coral tissue covered the straps and the colonies healed completely.

(A) Acropora cervicornis outplanting sites (B) Coral colonies attached to nails with plastic straps (C) Tissue covering straps on the base of the Coral. Calle-Triviño et al. (2020).

In 2013, the first two outplanted projects were carried out across zones T1 and T3 for a total of 214 outplanted colonies. In 2014, a new nursery (N2) was installed and two more outplanted sites were established (T2 and T4) for a total of 529 Acropora cervicornis outplanted colonies. In 2015, another four nurseries were established (N3, N4, N5 and N6) and a total of 743 corals were outplanted. After Hurricane Matthew in September 2016, two sites (T3 and T4) were closed and two new outplanted sites (T5 and T6) were established in protected areas. In 2017, a total of eight nurseries were established, with more than 26 000 cm of tissue, six outplanted sites, and 1446 outplanted colonies.

Each propagating Coral nursery had different ropes, frames, domes, tables, and figure structures that were maintained every 2 weeks to remove Coral competitors such as Macroalgae, Hydroids, and Bivalves and predators like Fireworms. Nurseries and outplanted sites had a depth of 12.5 m and occupied an area of approximately 200 m² except for the N6-Catalina nursery and T2-Coralina, both of which were between 2 and 5 m deep, respectively.

Calle-Triviño et al. used a methodology developed to determine restoration success elsewhere in the Caribbean by evaluating the growth, survival, and productivity of colonies installed in the nurseries and outplanted sites. They monitored sites during the 12-month period after their creation to compare them with the benchmarks provided for six programs in Florida and Puerto Rico. They proposed the following reference points for measuring the first year of Acropora cervicornis restoration: (1) the survival of Corals in the nursery must be greater than 80%, and (2) the survival of outplanted corals must be greater than 70%. Average productivity should be over 4.4 cm per year for Corals in nurseries and over 4.8 cm per year for outplanted Corals.

The methodology also considered a stop-light model based on the relative performance (mean) of each nursery and outplanted zone for each restoration criteria. In this model, values within 10% of the overall mean are considered green (desirable benchmark: no actions or improvement need to be made); values between 10% and 20% below the mean are considered yellow (caution: some adjustments must be made); and values 20% below the mean are considered red (action must be taken to improve methods, design, or site selection). These measures are proposed for sites in years without large-scale disturbances such as temperature anomalies or hurricanes. The authors suggested that these reference points, and possible subsequent adaptative management, are necessary to fully evaluate the long-term success of coral restoration and species recovery programs.

Growth and survival data were taken quarterly, and coral from both nurseries and outplanted sites were individually labeled. Each of the branch fragments were measured to the nearest centimeter with a flexible ruler. Growth was expressed as Total Linear Extension in cm. The change in Total Linear Extension in one year (growth) was estimated as Total Annual Growth, which was considered to be equal to the Final Measure minus the Initial Measure.

Colony survival was determined by counting the number of colonies with some percentage of living tissue at the start of the study, and then 12 months later. If a colony was completely dead (100% dead tissue), we noted the presumed cause of mortality.

Annual productivity was considered to be the Total Annual Growth divided by the initial Total Linear Extension). This was calculated by only grouping together fragments that were alive during the entire 12-month period that grew positively; fragments with partial tissue loss were not measured. 

To describe the clonal diversity of the main nursery, samples were collected from three different structures: rope (60), frame (70), and dome (15). Since the Corals were was not arranged or divided by potential genotype, random Corals were sampled for genetic analysis. Calle-Triviño et al. collected 1 cm2 tissue samples from 145 colonies for genotyping. Collections were permitted by the Ministry of Environment and Natural Resources. Samples were placed in vials with 95% ethanol, stored, and taken to the Center for Scientific Research of Yucatan (CICY) for analysis. Once there, DNA samples were extracted using a DNeasy Blood & Tissue Kit (Qiagen, Hilden, Germany).

The mean survival of the fragments during the 12 months across all nurseries was 87.45%, with a range of 80.6–94.8%; sample sizes were 119 for N1, N2, N4, N5, N7, and N8; 98 for N3; and 102 for N6. The most common cause of mortality in nurseries was the presence of an accelerated tissue loss syndrome. Competition from Algae, Sponges, and Hydroids was less prevalent due to nursery maintenance practices.

The mean productivity value was 4.01 cm per year for the eight nurseries. The study did not evaluate the differences in growth metrics for fragment size (large, medium, or small), or the type of platform (floating or fixed). The mean survival of the six outplanted sites during the 12-month period was 71.55%, with a range of 57.3–83.3%. The most common cause of mortality during this period was sedimentation and predation by the Bearded Fireworm, Hermodice carunculata. The six outplanted sites’ mean productivity value was 3.03 cm per year; of these, T2 and T4 were the least productive.

The Bearded Fireworm, Hermodice carunculata, the most important predator of Staghorn Corals,  Acropora cervicornis, during Calle-Triviño et al.'s study. Fabrizio Fabroni/World Polychaeta Database.

Cyclonic activity was substantially high in 2016 and 2017, and three hurricanes impacted the study zone: category 4 Matthew (2016), and Irma & Maria (2017), both category 5. Hurricane Matthew caused damage to many of the nursery structures, with a loss of 35 structures in total in 2016.

The mean survival of all nursery fragments after the 2016 and 2017 cyclonic seasons was 35.06%, with a range of 16.96–52.07%. The main cause of mortality was the loss of nurseries structures, which hampered fragment rescue.

The mean survival of the outplanted colonies in four outplanted sites operating after Hurricane Matthew (2016) was 28.68%, with a range of 5.49–51.78%. Due to damage sustained from Mathew in 2017, the T3 and T4 outplanting sites were closed by the program managers. However, T2 was rehabilitated with fragments rescued from the same area, and two new outplanted zones were created (T5 and T6). The mean survival of the outplanted colonies after Hurricanes Irma & Maria (2017) was 61.57%, with a range of 46.66–83.17%.

Hurricane Irma, a catagory five storm, passing over the Dominincan Republic in 2017, imaged by the Geos 16 Satellite. NASA.

The results of Calle-Triviño et al.'s genetic analyses showed that the main nursery contained 32 multilocus genotypes in the 145 sampled colonies.

To assess the performance of the Acropora cervicornis restoration program in the Dominican Republic, Calle-Triviño et al. evaluated the growth and survival of nursery and outplanted Corals between 2011 and 2017. Theur analysis and interpretations were based on the relative yielding (mean) of each nursery and outplanted zone, based upon the stoplight model. Calle-Triviño et al. documented the results of the program during non-stress conditions and under stress caused by the strong 2016 and 2017 cyclonic seasons in Bayahibe. Additionally, the genotype characterization of coral propagated in nurseries suggest the presence of enough genetic diversity to continue program development.

Calle-Triviño et al.'s results showed high survival (over 80%) for 12 months across the eight nurseries. This indicates that the standards used for selecting coral nursery farming sites were appropriate. The methods used to propagate Corals (transport, structuring, implementation) have efficiently promoted survival and productivity and did not cause mortality. The frequency and methods used for maintenance and monitoring during the first year were also appropriate.

The annual productivity values for the six nurseries were over 4.4 cm per year. Calle-Triviño et al.'s results confirmed that the yield of each of these nurseries was optimal and growth rates were higher than those reported for wild Staghorn Coral, fulfilling the main objectives of the nurseries to maximize growth rates and minimise mortality.

However, considering Calle-Triviño et al. randomly collected the genotypes used for all nurseries and used the same propagating structures (fixed and floating), nurseries N3-Dreams (1.28) and N6-Catalina (1.30) had the poorest performances in terms of Coral growth (i.e., over 4.4 cm per year), indicating that the sites chosen for these two nurseries did not foster Coral growth. These results may be due to the fact that the N3 nursery site had low water circulation and high sedimentation, factors that may influence Coral growth. After Hurricane Matthew, N3 was moved a few meters offshore so its Corals could increase their growth rates. The N6-Catalina nursery site receives a large number of daily tourists and watershed discharges with large quantities of sediments, nutrients, and urban wastes from La Romana city.

N6 was one of the nurseries most affected by Hurricane Matthew, losing 84% of its structures. Since it is a shallow and unprotected site, it had a survival rate of 15% after the 2017 hurricane season. Additionally, the time between these two hurricane seasons was very short, and the surviving Corals failed to adapt and recover.

Three of the eight nurseries and two of the four outplanted sites suffered significant damage from the strong cyclonic seasons. Although the survival of the eight nurseries averaged 35.07%, Calle-Triviño et al.'s results are encouraging when compared to the mortality reported for Puerto Rico’s nurseries and outplanted sites (over 90%) after Hurricanes Irma and Maria. 

Calle-Triviño et al.'s results indicate that the Coral nurseries are genotype reservoirs better adapted to the strong environmental changes occurring in 2016 and 2017. Nurseries have served as havens in the face of disease outbreaks, storms, and extreme temperatures. They also serve as production sites for Coral larvae, Fish, and other organisms, contributing to overall ecosystem diversity.

In 2015 and 2016, restoration activities were supplemented by assisted fertilisation, suggesting that Acropora cervicornis colonies from the main nursery can reach sexual maturity and release their gametes. Likewise, gametes and larvae raised from nursery populations can provide key resources for research on assisted evolution and genetic engineering. Nurseries can generate thousands of planula larvae to act as larvae dispersion centres, which in turn could establish larvae connectivity routes between Coral patches.

Calle-Triviño et al.'s data indicate that genetically diverse populations within a nursery are valuable due to the assisted fertilisation success they provide to nursery and outplanted stock. It should be noted that additional studies and information are needed to determine the compatibility of the known genotypes and the success of their offspring.

The main objectives of the nursery phase include minimising Coral mortality and maximizing productivity. However, outplanted sites’ primary purpose is to establish genetically diverse populations.

The challenge is to ensure that degraded reefs increase their structural complexity by outplanting Corals that have been raised in nurseries. These Corals can reproduce sexually, thereby increasing genetic diversity and support for the establishment of other species. Calle-Triviño et al. expect the formation of biological corridors, essential for ecosystem connectivity and indispensable for increasing functional biodiversity and reef resilience.

Calle-Triviño et al.'s results showed high survival rates (over 70%) during the first 12 months for four of the six outplanted sites. These rates match the benchmark proposed for the survival of outplanted Corals during the first year). Only two of the outplanted sites (T3 and T4) were more than 10% lower than the mean. Mortality in these two zones was associated with the presence of predators, mainly Fireworms. These two zones are adjacent, separated by less than 500 m. It is possible that ineffective maintenance and cleaning of these two zones allowed the fast growth and spread of Fireworms.

As for annual productivity, four outplanted zones were within the benchmark (4.8 cm per year) suggested for Florida and Puerto Rico. However, two outplanted sites were at high risk (i.e., under 4.8 cm per year), indicating that the selected sites did not provide a favorable environment for Coral establishment and growth. Zone T2-Coralina is particularly vulnerable because it is very close to the urban zone (500 m) and is thus directly impacted. Moreover, boats travel through and dock in the area. Although water in this zone is in constantly moving and circulating, the site is shallow (about 2–5 m). The fragment genotypes were collected in deeper areas and were maintained at the same depth in nurseries. Calle-Triviño et al. could not predict the nursery yield because it did not always correlate with yield of the outplanted sites. Additionally, genotypes may have very different growth rates in different environments.T2-Coralina was the zone most affected by the strong 2016 and 2017 cyclonic seasons.

Calle-Triviño et al.'s results suggest that the main nursery had higher genotypic diversity (32 different genotypes) compared to other nurseries in the Dominican Republic (13 genotypes in the Punta Cana Ecological Foundation) and Florida (24 genotypes). The high genotypic diversity represented within this nursery, as well as the compatibility of those genotypes successfully demonstrated by the assisted fertilisation initiatives in 2015 and 2016, confirm that the restoration program in the Dominican Republic should be expanded to maintain and increase diversity.

These results are ecologically important because the main nursery populations represent a functional unity (source of Coral) for Coral Reef recovery through an active conservation response. Coral can be very useful in increasing genetic diversity and population density when outplanted to degraded or disturbed sites, and they can also contribute to increased sexual reproductive success.

The dominant reproduction mode of a specific population of species is crucial as it influences environmental stress management with long-term permanence. This must be considered when developing management and restoration strategies to protect and preserve species. The distribution of the clonal individuals identified in the main nursery, as well as the high diversity of genets found in this study, suggest that genotypes can help develop and improve the restoration program in the southeastern part of the island. Different genotypes planted with enough proximity can allow cross-fertilisation during massive spawning events. This is also relevant for restoration programs.

Moreover, restoration efforts should include information on the management and handling of species produced by genetic studies. Genetic patterns can guide conservation actions to obtain more resistant individuals able to cope with dramatic environmental changes, diseases, and pollutants, thus increasing genetic viability and preserving adaptive potential. Calle-Triviño et al.'s genotype identification established a baseline that will allow for the future spatially distributed selection of colonies in outplanted sites. This is also useful for future studies on genotype resistance against different stressors, such as high sedimentation, temperature increase, and predation by Fireworms.

Calle-Triviño et al.'s work documented the growth and survival of Acropora cervicornis Coral nurseries and outplants in southeast Dominican Republic. Calle-Triviño et al. believe that working together with researchers, practitioners, students, community volunteers, environmental authorities, and the tourism industry creates a higher level of Coral Reef conservation efforts in the region. They recommend that these alliances be strengthened for the sake of Coral Reefs, and that the systematic long-term monitoring of outplanted sites be continued, to build a scientific model helpful for studying spawning, improve the understanding of current functional aspects of these habitats, and provide information on the system’s stability and resilience.

When considering the predicted persistence, recovery, and extinction risk of Acropora cervicornis, intrinsic characteristics and external threats are important factors to consider. This species is at risk because of its continuous decline in abundance and the permanence of its threats. 

Although Acropora cervicornis has persisted at extremely low levels of abundance, the recovery of this species may not be possible due to the permanence of its stressors. Therefore, active restoration efforts like the one described in Calle-Triviño et al.'s study are necessary.

The restoration program examined in Calle-Triviño et al.'s case study has provided a number of benefits for the local ecosystem and economy, such as: (1) maintaining genetic diversity in nurseries with 32 available genotypes, (2) creating outplanted sites that have contributed to the rapid creation of fish and invertebrate habitats that would otherwise take decades to form, (3) providing a sustainable source of Corals for experimental research, and (4) providing unique volunteer and employment opportunities for local communities interested in participating in the restoration process.

Calle-Triviño et al. believe that the regional restoration benchmarks for Acropora cervicornis used can be widely applied in the comparison of programs across the Caribbean.

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Utilising undergraduate research to hunt for gold-precipitating Bacterial lineages.

The potential benefits from the study of the unique abilities of Bacteria to everyday Human life is ever more obvious. Bacteria are used industrially in food preparation, drug production, waste treatment and many other roles. Advances in biotechnology techniques have facilitated the use of known Bacterial species and their enzymes, proteins and pathways. For example, it is now possible, and indeed not very difficult, to identify genes of interest in a bacterial species, clip those genes out of that species and insert them into another work horse species of Bacteria to allow the products of those genes to be produced industrially. Ironically, as our ability to harness the power of Bacteria becomes ever more sophisticated, one of the key challenges is still finding the useful Bacteria in the first place. In a world with as many as a trillion Bacterial species, how does one speed the discovery of Bacterial species with a particular use or even simply strains of a particular bacterial taxon with sequences of interest? One approach is to engage citizen scientists. In as much as the first step in the discovery of novel, useful microbes is often collection from nature, collections made by the public have the potential to speed up this key and often rate-limiting first step. What is more, in a rapidly interconnected digital era, the potential for truly global projects that rely on hundreds, thousands, or even hundreds of thousands of individuals is ever greater.

In a paper published in the journal PeerJ on 14 April 2020, Noah Riley of the Department of Biological Sciences at North Carolina State University, Carlos Goller, also of the Department of Biological Sciences and of the Biotechnology Program at North Carolina State University, Zakiya Leggett of the Department of Forestry and Environmental Resources at North Carolina State University, Danica Lewis and Karen Ciccone of North Carolina State University Libraries, and Robert Dunn of the Department of Applied Ecology at North Carolina State University, the Natural History Museum of Denmark at the University of Copenhagen, and the German Centre for Integrative Biodiversity Research, describe the results of a study using a citizen science approach to to detect new species of the gold-precipitating Bacterium Delftia, on a university campus.

Citizen scientists contribute data to many publicly-accessible projects, from birdwatchers helping conservation efforts with the e-Bird project, game enthusiasts folding proteins for the FoldIt project, to homeowners exploring the microbial diversity in their houses through the Wild Life of Our Homes project. Additionally, projects like the Science Education Alliance - Phage Hunters Advancing Genomics and Evolutionary Science and Tiny Earth engage students in large research projects as part of course-based undergraduate research experiences. Citizen scientists, Riley et al. argue, can also help discover bacteria with novel, useful traits.

Delftia is a genus of Betaproteobacteria first discovered in the city Delft, where bacteria themselves were discovered by Leeuwenhoek. Delftia has genes capable of precipitating gold by excreting a metabolite called delftibactin. Gold in solution as gold chloride is toxic to bacteria, so Delftia has evolved this novel mechanism for precipitating aqueous gold out of solution to nontoxic solid gold nanoparticles. This mechanism has obvious potential uses in gold recycling in used electronics, gold mining, and urban waste, but to date, the existing genetic diversity of Delftia in strain collections is modest. There are only six known species of Delftia. Full genome assemblies exist for four of these species within the National Center for Biotechnology Information database. Discovery of novel Delftia species and their relatives has the potential to better elucidate variations in Delftia genetic sequences, especially within the gold precipitation gene cluster and other industrially and human health related sequences. The more information about these gold precipitation genes, for example, the greater potential for using Delftia or its genetic potential to recycle our electronics and make mining more sustainable.

A colony of Delftia acidovorans. Khalifa et al. (2019).

The Wolfpack Citizen Science Challenge for Spring 2018 was a collaborative project to document the presence and genetic diversity of Delftia spp. across the North Carolina State University campus and create a scalable and interdisciplinary model to continue learning about this and other organisms. In addition to involving students in two introductory courses in the initial data collection, we also involved students in two upper-level courses in the downstream study of the microbes detected during
the Challenge.

Participants were primarily recruited from two courses, ES 100: Introduction to Environmental Sciences (176 students) and LSC 170: First Year Seminar in the Life Sciences: Meet Your Microbes (20 students). However, anyone interested was able to obtain a sampling kit and participate. A post-event survey indicated that 96% of the participants were required to participate as part of a course and that 48% were currently enrolled as Science, Technology, Engineering and Mathematics majors.

Three events were held to create excitement and share results from the challenge. In January, the Challenge was launched with a public event attended by 19 people, in which Goller and Riley shared information about Delftia acidovorans found in sinks, drains and soil and encouraged members of the campus to think critically about the microbial communities around us. In March, the sequencing data were shared with the campus community at an event at which participants used the National Center for Biotechnology Information Basic Local Alignment Search Tool to find regions of similarity between the discovered sequences and those deposited in the National Center for Biotechnology Information database. This Basic Local Alignment Search Tool workshop was attended by 55 people. In April, results of the project were shared at a closing event open to the campus and general public, attended by 30 people. 

Participants registered as teams of up to five members and were provided kits with instructions and materials to collect samples: three swabs and two 50 millilitre conical tubes for soil samples along with gloves, plastic spoons for scooping soil, alcohol swabs to sanitise the soil collection spoons and labels for samples. Approximately 40 kits were distributed and over 150 swab and soil samples were received between 30 January and 14 February 2018. Samples were delivered in person to either the Biotechnology Program teaching laboratories or the North Carolina State University Libraries front desk. Samples were stored in −20°C freezer until ready for metagenomic DNA extraction. Along with physical samples, metadata including location descriptors and latitude–longitude data were submitted online through a customized SciStarter citizen science website. Students’identifying information was removed from samples and a numerical identity was assigned.

Participants were provided with detailed instructions on how to sample environments around the campus and use the sampling kit. Participants were instructed to use the swab to sample a safe location and immediately place the swab in the transport container. Students collected soil samples with the provided tube and spoon while wearing disposable gloves. For processing of samples, students in molecular biology courses were trained in lab safety procedures and given a document detailing the potential hazards and safety procedures used in the teaching laboratory. For all extractions and qPCR reactions, students wore provided disposable lab coats, safety glasses and gloves, and disinfected all surfaces before and after use.

Metagenomic DNA was extracted from samples using the Invitrogen PureLink Microbiome DNA Purification Kit according to the corresponding protocol for swab and soil samples.Soil was transferred from collection tubes to bead tubes with alcohol-sterilised metal scoops. Swab tips were cut off into bead tubes with alcohol-sterilised metal scissors. Samples were lysed and homogenized by heat, bead beating and lysis buffer. After purification, samples were eluted in 50 μl of elution buffer. DNA concentration was determined spectrophotometrically using a ThermoFisher NanoDrop 2000c instrument and normalized to five ng/μl. Samples were matched with descriptive location data in an online spreadsheet using information submitted on the SciStarter website. Isolations were performed by Noah Riley in batches of 12–24 samples.

An Eppendorf epMotion 5075 TC liquid handler was used to set up quantitative real-time polymerase chain reaction DNA amplification reactions with New England BioLabs Luna Universal Probe qPCR reagents, primers and double-quenched probes. Quantitative  polymerase chain reactions were run on a Bio-Rad CFX Connect instrument and data were exported as spreadsheets with cycle threshold values for each reaction. Samples were screened for the quantity of Delftia present using double-quenched, Delftia-specific primers and probe for a portion of the unique gold biomineralisation metabolite production system (the 'gold gene'). Presence and abundance of Delftia were then confirmed with a second set of primers and probe for a putative Delftia-specific toxin–antitoxin sequence unique to Delftia spp.. Reactions were set up in duplicate along with an 8-point, ten-fold dilution standard curve with 'gold gene' standard beginning at 40 pg/μl and toxin–antitoxin sequence standard at 30 pg/μl.

Undergraduate juniors and seniors and first- and second-year graduate students enrolled in an upper-level High-throughput Discovery 8-week lab module programed an epMotion 5075 TC liquid handler with the quantitative polymerase chain reaction script, prepared metagenomic samples for quantitative  polymerase chain reaction and calculated Delftia copy numbers using the quantitative  polymerase chain reaction cycle threshold data. Students were provided a spreadsheet template with detailed explanations and information on the use of a standard curve for calculation of absolute copy numbers of target sequences. Data were shared with students and groups of three to four were tasked with determining copy numbers for one 96-well polymerase chain reaction plate containing: 23 genomic DNA samples tested in duplicate along with an 8-point standard curve and negative buffer only controls. Multiple groups analysed the same samples to confirm the results and copy number trends were further supported by analysing quantitative  polymerase chain reaction data for the same samples with a primer set for the single-copy Delftia-specific toxin–antitoxin sequence. Data were then analysed as a class and shared with Danica Lewis for visualisation and dissemination of the results to participants and the public. Samples with the highest Delftia copy number using both primer sets were selected for further analysis of the unique gold gene sequence.

For 20 samples with high Delftia counts, a portion of the gold gene sequence was amplified using primers Seq7 and Seq8 and the New England Biolabs Q5(R) High-Fidelity 2X Master Mix. The amplified portion of the gold gene was selected because it is highly specific to Delftia and based on current sequence database information, varies slightly between known species and strains, allowing for identification from metagenomic samples. The target Delftia sequence is 1045 base pairs in length. Of the 20 tested samples, 17 produced sufficient PCR product for sequencing and were sent to the North Carolina State University Genomic Sciences Laboratory for Sanger DNA sequencing using primers Seq7 and Seq8. Amplicons (pieces of DNA or RNA that are the source and/or product of amplification or replication events) were sequenced from both directions and sequences were trimmed based on stringent quality settings to match existing sequences in the National Center for Biotechnology Information database. The sequencing data were shared with the campus community at an event at which participants used the National Center for Biotechnology Information Basic Local Alignment Search Tool to find regions of local similarity between the discovered sequences and those deposited in the National Center for Biotechnology Information database. This allowed participants to identify which Delftia species and strains best matched the samples that were sequenced.

The Google Maps Fusion Tables extension was used to create a heatmap of Delftia presence and abundance across campus and Tableau Public software was used to create an interactive map. Participants were invited to explore the data and evaluate which samples had the highest amount of Delftia. Students in the courses involved in sampling and analysis were shown the results and asked to discuss future research questions.

Map showing the sites at which Delftia spp. was sampled on the North Carolina State University Campus. Danica Lewis/Tableau Public.

Over 150 samples were received from participants. Of these, 135 were labeled correctly and matched with the online SciStarter database containing sampling location descriptions and latitude–longitude coordinates. Through quantitative  polymerase chain reaction analysis using primers and probe Seq1, Seq2, and Seq3, 125 samples (92.6%) had detectable quantities of the target Delftia 'gold gene' DNA sequence. Quantities of Delftia within samples were confirmed using the toxin–antitoxin sequence quantitative  polymerase chain reaction primers and probe Seq4, Seq5 and Seq6. The 20 samples with highest Delftia counts were primarily swabs from sinks and drains. In contrast, the samples with the least Delftia DNA tended to be those from soil samples and outdoor locations. However, it is worth reiterating that nearly all of the samples contained some Delftia, a relatively understudied genus of Bacteria.

Riley et al. next compared the Delftia gold gene sequences in the samples to those of sequenced strains. Collectively, the sequences from their samples were most similar to those of Delftia tsuruhatensis strain CM13, Delftia acidovorans strains ANG1 and SPH-1, or Delftia acidovorans strain RAY209. Differentiation between Delftia acidovorans strains ANG1 and SPH-1 was not possible as each matched query had the same identity, query coverage and E value results for both strains. However, for strains of Delftia tsuruhatensis CM13 and Delftia acidovorans RAY209, the sequences matched with highest probability to each, respectively. None of the samples were close matches for the other sequenced Delftia species of Delftia deserti, D. lacustris, Delftia litopenaei, Delftia rhizosphaerae, or other strains of Delftia acidovorans and Delftia tsuruhatensis. A total of 14 out of the 17 sequences had less than 97% sequence identity with the Delftia strains they most closely matched.

Riley et al. sought to simultaneously test whether they could engage students campus-wide in a citizen science style microbial research project and in doing so, understand the distribution and diversity of strains of one particular Bacterial genus, Delftia. They were indeed able to engage students from diverse majors across campus. In doing so, they discovered that some sampling sites had many more Delftia counts than did others, that Delftia was relatively ubiquitous and that some of the strains we identified had gold genes that appeared relatively divergent from those known from the literature. Although they were unable to accurately determine the diversity of Delftia strains present, this unanswered question presents a new challenge and opportunity for our citizen science and Delftia research efforts.

Collectively, the quantitative  polymerase chain reaction, Sanger DNA sequencing and Basic Local Alignment Search Tool comparison results showed that strains of Delftia are diverse, abundant and frequent (found at many sites) in environments in and around the college campus. Based on available genomic sequences deposited in the National Center for Biotechnology Information database and partial sequencing of the highly conserved gold gene, the strains students discovered best matched the reference strains Delftia tsuruhatensis CM13 and Delftia acidovorans ANG1 and SPH-1. However, 14 of 17 samples contained strains that were a 97% or lower match to strains in the National Center for Biotechnology Information database. Riley et al.'s suspicion is that these strains represent uncharacterised genetic diversity among strains in Delftia’s gold gene. However, because Riley et al. sequenced from complex environmental samples they can’t preclude the possibility that some of this variation is due to cases in which the forward and reverse sequences obtained were from different Delftia species or strains in the sample.

The sequenced Delftia gold gene from many of the participant samples matched well to known Delftia species, but some samples matched two different existing strains equally well. For example, samples from 7-1 to 24-1 were equally similar to the strains Delftia acidovorans ANG1 and SPH-1. Clearly further work can be done to sequence additional portions or the entire genomes of these samples to identify what known strain is present or discover a new lineage of Delftia. More extensive community analyses of the samples using both targeted (16S rRNA gene) and whole genome shotgun sequencing would aid in the identification of which microbes associate with the presence of Delftia and the identity of the gold sequences in the environment, respectively. Additionally, high-throughput sequencing approaches such as Hi-C from Phase Genomics or Nanopore single-molecule long-read sequencing can be employed to attempt to sequence and assemble the entire Delftia genome in metagenomic samples positive for Delftia by quantitative  polymerase chain reaction. Ultimately, selective media capable of isolating and identifying Delftia would allow us to increase our collection of Delftia strains for basic functional studies and genome sequencing.

Riley et al.'s sequencing results best matched the species Delftia acidovorans and Delftia tsuruhatensis, both of which have been found in environments similar to those they studied. Delftia acidovorans was originally discovered in soil and has been found in drains, waterspouts and showerheads in the built environment. Delftia tsuruhatensis was first discovered in a wastewater treatment plant and has been found in similar locations along with Delftia acidovorans. The Delftia species Riley et al. did not encounter in their study are species that have so far been associated with more restricted habitats. Delftia deserti has been found to inhabit desert environments, Delftia lacustris in lake water, Delftia litopenaei in pond water, and Delftia rhizosphaerae in the rhizosphere of the Gum Rockrose, Cistus ladanifer, a Plant native to the Mediterranean region. The apparent ubiquity of the genus Delftia hides the reality that individual species appear to show considerable habitat restriction. In the future, it would be interesting to understand which traits and genes of individual Delftia species confer the ability to survive in particular habitats.

It is unclear the extent to which the life history of Delftia in the above habitats is the same as that of Delftia in the built environment of a college campus. Nor is it well understood whether the presence of Delftia in water systems is problematic or potentially beneficial. Like many Bacterial taxa, Delftia species are recorded as opportunistic pathogens that can infect hospitalised or immunocompromised patients. However, there is no indication that Human bodies are a common habitat for this genus. Instead, in buildings such as those we sampled it appears to be much more common in water systems; in drains, showerheads and downspouts. In as much as the ecological conditions of water systems differ greatly, it is possible that a comparative study of water systems, such as those that are or are not chlorinated, might reveal more about the built environment natural history of this organism.

Riley et al.'s approach kindled campus-wide student interest in microbial diversity and molecular biology techniques through the excitement of discovering this unique microbe in places that students frequent on campus. Groups of students from various academic disciplines and courses produced and analyzed samples that contributed to a large public dataset. The findings helped teach the student community about Delftia and also reinforced the importance of the collaborative nature of scientific discovery. The success of this project, in terms of the documentation of Delftia’s distribution helps to validate Riley et al.'s general approach. In addition, this approach has the potential to encourage future students to participate. Riley et al. aim to continue the challenge of accurately identifying new Delftia lineages and engage others by expanding the sampling opportunity to a multi-section first-year English class that is required for all undergraduate students on the campus. Using a similar approach and incorporating the expertise of faculty in the English department, they will engage students in writing tasks related to the project. Additionally, an upper-level metagenomics course will tie into this endeavor by processing, sequencing and analysing the microbial communities in samples with high numbers of Delftia sequences. With relatively minor changes to the course schedules and curricula, 100 more students per semester can participate, learn and contribute to the project. Riley et al. are creating resources that are accessible for other faculty and campuses to implement this project and share findings. For this, students participating in the project are writing The Delftia Book, and Riley et al. have created a group for instructor resources on the QUBES web portal. Liquid handlers can be cost-prohibitive, but less expensive models such as the Opentrons OT-2 are available, and Riley et al. are developing scripts for this instrument. Student groups in lab-based courses can always set up quantitative polymerase chain reactions manually to participate in this project.

As the future plans for integrating this project into courses indicate, enthusiasm for the project was high among Riley et al.'s colleagues and grew as the project proceeded. However, if they are to continue the project it is key that it continues to yield new scientific insights. Fortunately, this seems very likely to be the case. For example, although Delftia abundance was very patchy on campus, Riley et al. have yet to explain what factors account for such patchiness. Additional samples will help to have sufficient coverage across sample types to allow spatial models of Delftia diversity and abundance. In addition, Riley et al.'s results suggest that new variants of the Delftia gold gene and even new Delftia strains remain to be discovered. Conversely, there is a lack of genomic diversity represented in the National Center for Biotechnology Information database. By leveraging the enthusiasm of university students and staff, interconnecting courses and researchers, and using Riley et al.'s model pipeline, new lineages of Delftia can be rapidly identified and studied (e.g., groups of students cloning novel gold gene cluster into a host such as Escherichia coli or Yeast for functional characterisation). This will yield a better understanding of the ecological and environmental significance of these organisms and simultaneously help to connect students and faculty across campus in a common scientific project. Finally, it is of note that Delftia species, while little known, are of potentially great applied importance. In addition, they contain genes that allow many strains to precipitate gold. Given the many waste streams in which gold is present but hard to concentrate, this ability has the potential to be very useful moving forward.

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