Monday 31 May 2021

Tackling racial diversity in the geosciences.

The evolution of the modern geosciences was closely linked to the expansion of European colonial powers, at a time when it was widely believed, at least by the European ruling classes, that the land belonged to those who were willing to use its products. At this time little thought was given to the opinions or welfare of indigenous non-European peoples. This meant that, to a large extent, the geosciences developed as a means to understand the distribution of mineral resources, with a view to extracting them for the benefit of the colonial powers. This knowledge is still important; without an understanding of the distribution of mineral resources, equitable sustainable development would be close to impossible. However, in order for this knowledge to be used for the benefit of the whole community, then the geoscientists wielding it need to reflect that community, and include people from a wide range of people from different communities and walks of life.

Achieving diversity within the geosciences requires robust measures to promote inclusivity, particularly within the former colonial powers. The geoscience disciplines in the Global North are still very much a white discipline, which appears to be a result of both subject-specific issues, and the wider problems of systemic racism within academia. For example, in the US just 6% of doctorate degrees in geoscience disciplines are awarded to students from under-represented minority backgrounds (defined in the US as American Indian or Alaska Native, Black or African American, Hispanic or Latino), despite the fact that these groups make up 31% of the total population. In order to become more inclusive, the biases and hostile environments that have led to this imbalance need to be addressed, and institutions need to work harder to both recruit people from a wider range of backgrounds, and to retain such recruits throughout their careers.

The US actively records data on the backgrounds of students achieving post-graduate qualifications in the geosciences (and other disciplines), but such information is less widely collated in other nations of the Global North.

In a paper published in the journal Nature Geoscience on 29 April 2021, Natasha Dowey of the Department of the Natural and Built Environment at Sheffield Hallam University, Jenni Barclay of the School of Environmental Sciences at the University of East Anglia, Ben Fernando of the Department of Earth Sciences at the University of Oxford, Sam Giles of the School of Geography, Earth and Environmental Sciences at the University of Birmingham, Jacqueline Houghton of the School of Earth and Environment at the University of Leeds, Christopher Jackson of the Department of Earth and Environmental Sciences at the University of Manchester, Anjana Khatwa of Wessex Museums, Anya Lawrence, also of the School of Geography, Earth and Environmental Sciences at the University of Birmingham, Keely Mills of the British Geological Survey, Alicia Newton of the Geological Society of London, Steven Rogers of the School of Geography, Geology and the Environment at Keele University, and Rebecca Williams of the Department of Geography, Geology and Environment at the University of Hull, seek to address some of the issues surrounding inclusivity in the geosciences in the UK. Dowey et al. use data from the UK Higher Education Statistics Agency, which paints what they describe as a 'dismal picture' of inclusivity in the UK, and further note that similar data would be very hard to collect for most other European countries, as such data simply isn't collected at all.

Four of the authors of the paper come from BAME backgrounds (Black, Asian and minority ethnic, the terminology currently used by the UK Higher Education Statistics Agency, but which Dowey et al. recognise homogenises different identities and can obscures experiences felt by one race or ethnicity). The majority of the authors have never been the victims of direct racism, but several hold responsibilities for equity, diversity and inclusion with different organisations, and all are concerned about the current situation, and wish to challenge geoscience leaders in both industry and academia to listen to a wider range of voices, address existing biases and inequalities in the field, and build a more inclusive and accountable culture within the geosciences as a whole.

The UK education system seldom if ever acknowledges the connection between the growth of our modern understanding of the geosciences (or geography in general) and the colonial expansion of the European powers. Furthermore, geoscientists are generally depicted as white men involved in a rugged, outdoors activity, something generally discouraging to people from minority backgrounds. This is reflected in the promotional materials produced by UK universities and geoscience organisations with a public engagement remit, which tends to be filled with images of white students exploring dramatic landscapes.

A recent survey by the Geological Society of London found that 60% of undergraduate geology students cited a lifelong interest in the natural environment. However, access to such environments is often governed by the environment in which one grows up, with children growing up in urban areas and in particular those from low income households, typically having far less ability to interact with the natural environment. Demographic studies of the UK suggest that over 98% of Black African, Pakistani and Bangladeshi people live in urban locations, and that Pakistani, Bangladeshi, Chinese and Black children are more likely to live in low income households that White children. A study by the UK Department for Environment, Food and Rural Affairs found that 18% of children living in the most deprived areas never visited the countryside, and that those from Black and Asian families did so the least. Furthermore, a career in the geosciences is generally less likely to be seen as financially secure that a career in other professions by members of many minority communities.

Analysis of applications data has found that high-tariff, research-led, institutions were less likely to accept that students from BAME backgrounds than White students with similar qualifications. As an example, Dowey et al. cite the case of Oxford University, where it has been shown that BAME applicants are 5.8% less likely to receive a placement offer on mathematical, physical and life sciences courses than White students with similar qualifications. Overall Black students make up 3.9% of the toral number of students at high-tariff universities (universities that require high pre-university grades to gain entrance), and 12.2% of students at low-tariff universities (universities that require lower pre-university grades to gain entrance). Once enrolled, Black students are significantly less likely to gain either a first or 2.1 degree than White students. This in turn impacts the number of Black students gaining entrance to PhD placements, where there is a marked preference for students who have completed their undergraduate degrees at high-tariff universities, and application processes often reflect the candidate's access to resources as much as their actual ability, which strongly stigmatises students from less well off communities. In 2018/19 only 9% of UK Research and Innovation funded studentships, and only 6% of Environment Research Council studentships, were awarded to ethnic minority candidates, at a time when 19.4% of 18–34 year olds identified as BAME.

Representation of BAME students in the geology, environmental science and physical geography, shown alongside data for the overall physical sciences subject area and ethnicity data from the 2011 UK Government Census. UK Higher Education Statistics Agency data, based on full-time ‘all undergraduate’ and full-time ‘postgraduate research’ categories and are a five-year mean of data from 2014/15 to 2018/19. Dowey et al. (2021).

Dowey et al. also note that a lack of positive role-models within the field also probably serves as a discouragement to BAME students. Only 10.8% of UK professors identify as BAME, falling to 3.9% in Earth, marine and environmental sciences; the second lowest of any science, engineering and technology discipline. This creates an ‘institutional whiteness’ that can leave BAME students feeling isolated within institutions, and leaves the few BAME staff burdened with the additional responsibility of advancing equality without any meaningful reward.

Studying geosciences can also present additional, subject-specific, boundaries to BAME students, including cultural problems, such as co-educational residential trips and a prevalent ‘alcohol culture' in many geoscience departments and at conferences, as well as the high costs associated with fieldwork, which can impact students from economically disadvantaged communities, and more obvious problems of racial harassment, which can be a problem for students carrying out fieldwork in some areas.

These boundaries do not exist in isolation, students may also be impacted by other issues relating to gender, sexuality, disability, class, or nationality, and therefore increasing the accessibility of institutions to BAME students should be seen as part of a wider drive to make the geosciences an option for a wider range of minority groups.

In recent years there has been a drive for academic institutions to address their past links to colonialism. Within the geosciences, geologists such as Adam Sedgwick and Henry de la Beche are often cited as founding figures within the discipline, without mention of their links to the slave trade. Mapping and surveying are (inevitably) taught as a part of geosciences courses, but seldom with any mention of how these techniques were developed as part of a wider British colonial expansion, nor with reference to the ongoing destruction of sites deemed important by indigenous cultures by mining or civil engineering projects. Moving forward, Dowey et al. hope that geoscientists will work more closely with social and historical scientists to find ways to find ways to teach these subjects in a positive way with a stronger emphasis on geoethics.

Adam Sedgwick (1785-1873), proposed the Cambrian and Devonian periods of the geological timescale, and is considered one of the founders of modern geology. He was a vocal supporter of the abolition of slavery, but is also known to have owned slaves on plantations in Jamaica, and upon the abolition of slavery by the British government, received £3783 1s 8d in compensation for the loss of 174 slaves. Thomas Philips (1770-1845)/The Adam Sedgwick Collection/Wikimedia Commons.

A traditional approach to the geosciences is often one in which a Western field scientist visits a location, removes samples (often with local help), takes them back to a Western institution for study, then publishes their results in an (often paywalled) Western publication, without input from, or acknowledgement of, local authors. Such work seldom takes into account the views of local populations.

The tenth of the seventeen United Nations Sustainable Development Goals is the reduction of inequality within and between countries. Achieving this is generally accepted as being impossible without developing a more sustainable society, something which has major implications for the geosciences. Teaching a more inclusive geoscience curriculum, which takes into account a wider range of cultural perspectives, should enable students of all races and ethnicities to participate in shaping the future of the discipline.

Universities and other institutions have the ability to invest resources in racially diverse promotional materials and ambassador schemes that reward outreach work, rather than simply relying on BAME students to fit in with existing structures. There are existing organisations, such as Black In Geoscience and Black Geographers, which promote the role of BAME people within the geosciences, and by working with these educational institutions can promote more diversity within the field. Inviting a more diverse range of people to deliver seminars and presentations within universities can make BAME workers (and other minorities) more visible within the field, and more work can be done to increase the diversity of faculty members, by implementing development opportunities aimed at such staff, to counterbalance existing pathways which tend to favour a narrower range of workers.

Such work also needs to take place at earlier stages in the education system, in order to better access to the natural environment for younger members of BAME communities. Natural heritage organisations should work more closely with such communities, possibly by working with organisations such as Black2Nature, run by youth campaigner and environmentalist Mya-Rose Craig, which has opened pathways enabling young people from deprived areas in Bristol to learn about birding, conservation and wildlife. Universities can also promote such access through targeted outreach activities.

Youth campaigner and environmentalist Mya-Rose Craig (aka Birdgirl). Black2Nature/Facebook.

There are a number of steps that can be taken to make fieldwork more accessible to ethnic minority students. Notably, fully subsidising the cost of field-trips and equipment costs would remove boundaries to fieldwork for students from low-income backgrounds, and carrying out racial risk assessments ahead of planned fieldwork. Staff can also benefit from anti-discrimination and allyship training, and all race-related incidents should be fully documented. Courses should also be carefully planned so that fieldwork requirements do actually relate to the intended learning outcomes; many professional bodies require a mandatory number of days of fieldwork for the accreditation of courses, which promotes the traditional image of White, male, students involved in macho outdoor fieldwork, but often does not greatly enhance learning outcomes.

Students from minority backgrounds can also be helped by creating ring-fenced opportunities which address their needs, such as funded research experiences, summer schools, internships and studentships. More can be done to work with schools, colleges and other universities, to make students aware of such schemes where they exist.

Funding organisations and institutions need to be held accountable for transparency in their recruitment processes, and members of interview panels need to understand the barriers to BAME students, in order to to ensure improved diversity in successful applicants. Demographic data on candidates at the application, interview, offer and acceptance stages, should be published, in order to provide a clearer picture of postgraduate recruitment diversity.

Efforts to improve diversity should not be seen as ending at recruitment; more resources should be allocated to training in equity and inclusion. Diversity 'champions' can support the interests of minority candidates and groups, and encourage institutions to reflect on practices which produce hostile environments.

Dowey et al. argue that universities and other higher institutions need to acknowledge the hostile environments that can exist within them, which can discourage BAME students from both applying to, and continuing within geoscience disciplines. In order to make sure efforts to resolve these problems are long-lived, evidence-driven research needs to be undertaken to make sure the causes of problems are well understood, and efforts should be made to collaborate with other subjects and bodies facing similar challenges, thereby sharing transferable solutions across the sector. Workers in higher education must address personal and structural biases, and strive to be actively anti-racist. Finally, Dowey et al. note that the less diverse a field is, the more prevalent implicit biases become, and that difficult conversations need to happen sooner rather than later in order to create a more diverse and inclusive geoscience research culture.

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Saturday 29 May 2021

Possible preserved eggs in Selkirkiid Worms from the Early Cambrian Xiaoshiba Lagerstätte of South China.

Over the past century the discoveries of numerous Cambrian Lagerstätten (such as the Burgess Shale and Chengjiang biotas) have given us remarkable insights into the functional anatomy, development, lifestyles and behaviour of the earliest Metazoan Animals. However, their reproductive anatomy and behaviour, for the most part remains unknown. Indeed, examples of reproductive behaviour from the entire Palaeozoic Era are rare, comprising a few strands and clusters of eggs, some scattered examples of brooding in Arthropods, and the possible embrio-structures seen in Orsten-type deposits from the Cambrian of Siberia and China. 

The Ecdysozoa is the single largest group of Animals today, comprising the vast Arthropod clade, plus worms such as the Nematoids and Scalidophorans (the group which includes the Priapulids). In Cambrian faunas this group seems to have been equally important, with Ecdysozoan Worms having apparently been a major part of all benthic communities, playing significant roles as bioturbators, predators and recyclers. The Scalidophorans are particularly well represented in the Burgess Shale, Chengjiang, and Qingjiang biotas.

Selkirkiid Worms are known from the Cambrian of North America, South China, and Greenland, and are probably stem group Priapulids (Worms more closely related to Priapulids than to any other living group, but which lived before the most recent common ancestor of all living Priapulids, or which are descended from such Worms but not the most recent common ancestor). They share several important morphological features with extant Priapulids, and other fossil Scalidophoran Worms, such as an eversible introvert lined with scalid rows and a circum-oral pharyngeal structure bearing teeth. However, Selkirkiids differ from Priapulids and other Scalidophorans in the presence of a conical tube, which with numerous, evenly spaced annuli, is open at both ends, encase the whole trunk, and presumably represents a cuticular structure secreted and renewed by underlying epidermal tissues. There are currently three named genera of Selkirkiids, Selkirkia from North America, Paraselkirkia from China, and Sullulika from Greenland, although it is likely that Paraselkirkia is a junior synonym of Selkirkia (i.e. these Worms should be placed in the same genus, and Paraselkirkia, having been used first, takes precedence and is the name which should be used.

In a paper published in the journal Geoscience Frontiers on 21 May 2021, Xiao-yu Yang of the Key Laboratory for Paleobiology and MEC International Joint Laboratory for Paleoenvironment at Yunnan University, Jean Vannier of the Université Claude Bernard Lyon 1, Jie Yang, also of the Key Laboratory for Paleobiology and MEC International Joint Laboratory for Paleoenvironment at Yunnan University, Deng Wang, also of the Université Claude Bernard Lyon 1, and of the Shaanxi Key Laboratory of Early Life and Environments and State Key Laboratory of Continental Dynamics at Northwest University, and Xi-guang Zhang, once again of the Key Laboratory for Paleobiology and MEC International Joint Laboratory for Paleoenvironment at Yunnan University, describe strucures which they interpret as eggs within the body cavities of the Selkirkiid Worm Paraselkirkia sinica, from the Early Cambrian Xiaoshiba Lagerstätte.

The fossils were collected from the Xiaoshiba section of the Hongjingshao Formation, roughly 3.7 km to the southeast of the village of Ala, in Kunming, Yunnan Province, and are dated to the Cambrian Stage 3 (known locally as the Canglangpuan), making them about 514 million years old. 

Paraselkirkia sinica is common in both the Chengjiang and Xiaoshiba biotas, being found at many locations in China, often in dense aggregations. Yang et al. collected about 200 specimens, all preserved as two-dimensional compressions, with pellet-like gut contents; this is fairly typical for Paraselkirkia sinica specimens from the Xiaoshiba, Chengjiang and Qingjiang Lagerstätten. Both internal features (such as the gut tract) and external features (such as the introvert, pharynx, and tube) have an underlying brownish, reddish or yellowish colouration, caused by iron oxide derived from the weathering of pyrite, which in turn was deposited on the organic tissues by the action of sulphate-reducing bacteria under anaerobic conditions. This is a reasonably common feature of Cambrian Lagerstätten, seen in deposits such as the Chengjiang of South China, and the Fezouata of Morocco.

Oocyte-bearing Paraselkirkia sinica from the Cambrian Stage 3 Xiaoshiba Lagerstätte. (a), (b) YKLP 12089: (a) incomplete specimen showing partly preserved introvert, digestive tract and oocytes; (b) close-up (see location in (a)) showing oocytes within possible tubular ovaries. (c)–(e) YKLP 12350: (c) nearly complete specimen showing partly preserved introvert; (d) interpretative drawing; (e) fluorescence image (close-up, see location in (c)) showing oocytes. (f, g) YKLP 12351: (f) incomplete specimen (introvert missing) with oocytes within the tube; (g) close-up (see location in (f)) showing the egg cluster. (h), (i) YKLP 12352: (h) complete tube showing oocytes; (i) close-up (see location in (h)) showing up to 30 eggs seemingly organised in longitudinal rows. Abbreviations: ann, annulation; ct, cuticular conical tube; dt, digestive tract; gc, gut contents; in, introvert; oo, oocytes; ph, pharynx; sc, scalid; tr, trunk. Scale bar: 1 mm (a), (c), (d), (f), and (h) and 500 μm (b), (e), (g), and (i). Yang et al. (2021).

Some of the 200 specimens collected by Yang et al. were empty tubes, but many showed the remains of soft parts. Notably, eleven had clusters of ovoid elements below the midline of the trunk, with relatively sharp rounded outline. These ovoid elements often appear as conspicuous dark spots, between 300 and 450 μm in diameter. In some cases these elements clearly lie on top of the intestine and are overprinted by the annulated pattern of the tube, which Yang et al. take to indicate that they were located within the interspace between the digestive tract and the inner body wall. These objects are not randomly scattered within the body cavity, but instead, form relatively coherent clusters, in some cases spread out in elongate clusters; in some cases these appear to be arranged on either side of the gut, though in others they are clearly only on one side.

Yang et al. believe that the consistent location, shape and size of these elements strongly point towards these being eggs carried within the body cavities of female worms. Element mapping of these clusters revealed the presence of carbon, aluminium, and silicon, as well as iron and phosphorus. Micro-computerised tomography revealed exquisite details of the scalids and digestive tract, but yielded no useful information on the clustered elements. However, when one cluster was subjected to fluorescence imaging this revealed possible external envelope, which was weekly fluorescent and had sharp external margins, and an inner core, which was more strongly fluorescent, and appeared to be detached from the outer envelope.

Paraselkirkia sinica from the Cambrian Stage 3 Xiaoshiba Lagerstätte: general morphology and brachiopod epibiont. (a) YKLP 12356, complete specimen showing body features and a poorly preserved Lingulate Brachiopod (arrowed) attached to the tube. (b), (e) YKLP 12354: (b) a Kutorginate Brachiopod (arrowed) attached close to the posterior opening of the tube; (e) close-up of the Brachiopod. (c), (d), (f) YKLP 12353: (c) similar attachment by a Lingulate Brachiopod (arrowed); (d) close-up of the Brachiopod; (f) micro-computed tomography image showing the attached Brachiopod. (g)–(i) YKLP 12355, specimen with complete tube and egg cluster: (g) general view; (h) close-up (see location in (g)) with the left three oocytes (arrowed); (i) micro-computed tomography image (showing poorly survived oocytes (arrowed). (j) YKLP 12085, micro-computed tomography image showing a complete, well-pyritised specimen showing detailed structures (e.g., introvert scalids, digestive tract, and the boundary between the tube wall and matrix (arrowed). Micro-computed tomography scanning resolutions for (e), (h) and (i) are 3.56 μm, 3.96 μm and 4.92 μm, respectively. Abbreviations: an, anus; ls, larval shell, others as above. Scale bars: 1 mm (a)–(c), (g), 500 μm (f), (h), (i), and 2 mm (d), (e), (j). Yang et al. (2021).

Twenty two of the two hundred specimens have a single Brachiopod, either a Lingulate or a Kutorginate, attached to one side of the posterior end of the tube. This is consistent enough to suggest there may have been some form of symbiotic association in life. As far as Yang et al. know, the only example of epibiontic symbiosis recorded from the Xiaoshiba Lagerstätte, although such associations have been documented from other Cambrian Lagerstätten.

Yang et al. interpret the clusters of rounded objects observed in Paraselkirkia as eggs within the body cavities of female individuals, based on their consistent location, shape and size, which are comparable to the positioning of eggs within extant Priapulids. There is no evidence that these structures are attached to the tissues of the body cavity, which would be expected in a parasite infection, and they are clearly different from the gut contents, which can be seen as elongated pellet-like elements. The elemental composition analysis revealed a similar composition to that seen in the brooded eggs of Cambrian Bivalved Arthropods from other locations, such as Waptia from the Burgess Shale and Chuandianella from the Chengjiang Lagerstätte. The carbon presnt probably represents underlying thin carbon patches or particles of organic origin. The innability of micro-computed tomography probably also reflects their chemical make-up, and could be indicative of a low concentration in iron oxides compared with that seen in other features of these fossils. The structures shown by fluorescence imaging appear to be an external envelope surrounding an interior core made of a different substance, possibly a yolk or nucleus.

In modern Priapulids, such as Priapulus caudatus and Maccabeus tentaculatus, the gonads (ovaries in females and testes in males) are paired structures located in the posterior part of the trunk, which is a similar position to the structures seen in Paraselkirkia. These gonads can reach large sizes, compared to the rest of the body, and in mature females often occupy a major part of the primary body cavity. In macrobenthic species fertilisation is external with males and females releasing gametes (i.e. sperm and eggs) into the water. Females typically release thousands of oocytes (unfertilised eggs) at a time, through paired urogenital ducts opening on either side of the anus. External sexual dimorphism is rare in Priapulids.

Female reproductive organs and oocytes in extant macrobenthic and meiobenthic Priapulid Worms. (a)-(e) Priapulus caudatus. (a) Live specimen (in sea water). (b) Dissected specimen showing paired ovaries in the posterior part of the trunk. (c), (d) Ovarian sacs bearing numerous oocytes and supporting structure. (e) Yolk spherules inside the oocyte (oocyte membrane removed). (f)–(h) Maccabeus tentaculatus. (f), (h) Specimen bearing paired oocyte clusters (seen in transmitted light, under alcohol). (g) General view showing introvert crowned with tentacles (specialised scalids). (c)–(e), (g) are scanning electron microscope images. Abbreviations: bc, primary body cavity; ca, caudal appendage; gd, gonoduct; om, oocyte membrane; os, ovarian sac; ov, ovary; soc, supporting ovarial cells; tt, tentacle; ud, urogenital duct; ys, yolk spherule; others as above. (a), (b) from the Gullmarsfjord, Sweden; (c)–(e) from the White Sea, Russia) and (f)–(h) from Cyprus. Scale bars: 1 cm (a), 2 mm (b); 100 μm (c), (d), (h) and 2 μm (e). Yang et al. (2021).

Macrobenthic (large, bottom-dwelling) Priapulids such as Priapulus caudatus and Halicryptus spinulosus typically produce thousands of oocytes with diameters of up to 60-80μm, from ovaries which consist of a large number of ovarial sacs suspended between the gonoduct and a muscular strand. Meiobenthic (small, bottom-dwelling) species, however, produce smaller numbers of oocytes from simple tubular ovaries, although these tend to be larger. For example, Meiopriapulus fijiensis typically produces eight oocytes, but these are up to 250 μm in diameter, Tubiluchus corallicola produces about 20 oocytes reaching about 80 μm in diameter, and Maccabeus tentaculatus produces eight eggs, about 100 μm in diameter.

Comparative diagrams showing female reproductive organs in extant Priapulid Worms and early Cambrian Paraselkirkia. (a) Macrobenthic Priapulid Priapulus caudatus. (b) Meiobenthic Priapulid Tubiluchus corallicola. (c) Early Cambrian Paraselkirkia sinica. (simplified reconstruction). (d) Outline of the three forms represented at the same scale (from left to right: Priapulus, Tubiluchus and Paraselkirkia). (e) Mature oocytes of the three forms at the same scale. Primary body cavity in light blue, ovaries in dark blue, oocytes in yellow, muscular tissues in light red (around pharynx), digestive tissues in light orange, cuticle in grey. Retractor muscles may be present in Paraselkirkia but are not represented. Abbreviations: rm, retractor muscle; s, solenocytes; others as above. Yang et al. (2021).

Like modern Priapulids, the Cambrian Selkirkid Paraselkirkia sinica shows no sign of external sexual dimorphism, and there is nothing to indicate that fertilisation would have been internal in this species, and it is therefore presumed likely that egg fertilisation and embryonic dervelopmet would have been external. This would imply that the structures seen in Paraselkirkia sinica, which are 300–450 μm in diameter, are non-fertilised oocytes, not developing embryos. A maximum of only about 30 eggs is seen in any individual examined, sugesting that Paraselkirkia sinica follows the small-number-of-large-eggs strategy seen in modern meiobenthic Priapulids, although it would quite clearly be considered a macrobenthc were it alive today. 

The oocyte clusters retain an cohesive appearance, suggesting that they were retained in an ovarian sac, prior to being released through the urogenital ducts. In meiobenthic Priapulids today the mature oocytes are held in place by the ovarian basal lamina, although these supporting structures such as this tend to decay rapidly after death. If similar structures were present in Paraselkirkia sinica, then they may have helped to prevent the dispersal of the oocytes throughout the body cavity, The structures revealed within the oocytes by fluorescence imaging are comparible with the nucleus of the oocytes of Priapulus caudatus, which is to say about 40% of the diameter. 

Selkirkiid Worms have been interpreted variously as burrowers that possibly lived vertically embedded in sediment, or possibly epibenthic tubicolous Worms. This makes them difficult to compare directly to modern Priapulids, which are almost exclusively active infaunal burrowers. One known modern example of a tube-dwelling Priapulid does exist, Maccabeus tentaculatus, however this species reaches a maximum size of 3 mm, and forms a flimsy cylindrical tube from agglutinated plant fragments, a structure quite different from the rigid, annulated, cuticular tube of Paraselkirkia sinica. The sedentary meiobenthic Maccabeus tentaculatus uses a crown of tentacles (which are modified scalids) to catch vagile microbenthic prey such as Copepods, its tube being essentially a camouflaging device. Paraselkirkia sinica does not appear to have been particularly sedentary; it was probably less motile than non-tubicolous forms, but had a well-developed introvert, suggesting an ability to move and possibly penetrate soft sediment. It is possible that its scalids and tube annulations were anchoring features used during locomotion and excursions into the sediment, and its tube appears to have been a primarily defensive structure.

The presence of Brachiopod epibionts living on Paraselkirkia sinica also suggests a predominantly epibenthic lifestyle. Brachipods feed by filtering food from circulating water with lophophoral cilia, making it impossible for them to feed in buried in the sediment. Assuming that Cambrian Brachiopods fed in a similar way to their modern counterparts (and there is no reason to believe otherwise), then they would have been highly unlikely to regularly form a close association with an infaunal Animal. Yang et al. therefore conclude that Paraselkirkia sinica was a semi-sedentary epibenthic Animal that occasionally explored the most superficial layers of the sediment. It is possible that external fertilisation took place within the sediment.

Assumed lifestyle and reproductive mode of Paraselkirkia. (a) Living at the water-sediment interface with a juvenile Brachiopod attached near the posterior end of the tube via a short pedicle. (b) Moving slightly below the water-sediment interface for feeding or protection (e.g. possibly during moulting). (c) External fertilisation; oocytes and spermatozoids presumably emitted within sediment. (d) In-situ development of larvae. Yang et al. (2021).

Modern Brachiopods have free-swimming larvae which settle om a range of hard substrates, including the shells of many groups of invertebrates, and metamorphose into a settled form which remains attached to the same surface for the remainder of its life. Research into the Brachiopods of the Middle Cambrian Burgess Shale strongly suggests that the Brachiopods present there had already adopted this strategy, adhering to the hard tissues of Sponges in order to survive in an environment dominated by soft muds. The Brachiopods of the Xiaoshiba Lagerstätte are about six million years older than those of the Burgess Shale, and again appear to already be preferentially attaching to hard substrates in a muddy environment. 

The Brachiopods attached to the Selkirkiid Worm tubes of the Xiaoshiba Lagerstätte are small, typically about 1 mm in diameter, suggesting these were either exceptionally small species, or early stages in the development of larger Brachiopods. Yang et al. favour the latter explanation, and suggest that larger Brachiopods are absent as Paraselkirkia sinica was actually a rather poor host, moving about and interacting with sediments in ways which made it unlikely a Brachiopod settling on its tube would survive to maturity.

It is unclear whether the relationship between Paraselkirkia sinica and the Brachiopods had any benefit to the Worm (i.e. was it true mutualism rather than simply commensalism). The preference of Brachiopods for a position close to the posterior opening of the tube is also enigmatic, with Yang et al. suggesting that such a position may have given the Brachiopod access to 'food particles' produced by the anus of the Worm.

Although fairly large for a Priapulid, Paraselkirkia sinica appears to show a mode of reproduction seen only in meiobenthic species (which seldom exceed 1 mm in length) today. Meiobenthic Priapulids invest a comparatively high amount in each offspring, ensuring each has a good chance of reaching maturity, Macrobenthic species today, however, produce a large number of offspring, but invest little in them as individuals, making it less likely that each individual will reach maturity, but more likely that some of them will. This later strategy makes more sense if the offspring have a high chance of being killed by things against which the adults cannot protect them, such as predation or physical damage from the environment. Adult Selkirkiid Worms do not appear to have a close ecological match today, but the similarity in reproductive styles with modern meiobenthic Priapulids does enable us to make some assumptions about the ecological pressures facing the species' juveniles.

The similarity between the basic organisation of the reproductive system in Paraselkirkia sinica and modern Priapulid Worms suggests that this organisation originated early in the history of the group. Possible embryonic and early post-embryonic Selkirkiid Worms have been suggested from the very base of the Cambrian. These are also quite large, comparable to the large oocytes seen in Paraselkirkia sinica, potentially suggesting that similar reproductive strategies may have originated by then.

Modern Animals show a very wide range of reproductive modes, which may have appeared independently in different groups Ecdysozoans are the largest single subdivision of the Metazoa today and were already an important and diverse group in the Early Cambrian. The discovery of a reproductive  system in Paraselkirkia sinica  brings the number of Ecdysozoans from the Early Palaeozoic where we know something about their reproductive systems to three. In Early Cambrian Waptid Arthropods egg clusters have been found carried symmetrically on either side of the female's body, which suggests paired gonads as in Paraselkirkia sinica. Copulatory organs have been preserved in Ostracods from the Early Silurian Herefordshire Lagerstätte, which suggest that these Arthropods had developed internal fertilisation by this stage. 

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Monday 24 May 2021

Partula lutaensis: A new species of Partulid Tree Snail from Rota Island, in the the Mariana Archipelago.

Partulid Tree Snails are found across the islands of the tropical Pacific, reaching their maximum diversity towards the eastern end of their range, with the genus Partula reaching its highest diversity in the Society Islands, and the genus Samoana reaching maximum diversity in the Samoan Islands, although it is thought that these Snails originated further to the west. The Mariana Archipelago is a crescent-shaped chain of 15 volcanic islands extending roughly 2520 km from Farallon De Pajeros in the north to Guam in the south. These islands were long thought to be home to six species of Partulid Snails. Partula radiolata and Partula salifana were known only from Guam, Partula desolata, described from sub-fossil shells and probably extinct was known only from Rota, Partula langfordi was known only from Aguigan, and may also now be extinct, Samoana fragilis was known from both Guam and Rota, and Partula gibba known from seven islands, from Guam, in the south, to Pagan Island in the north.

In 2017 David Sischo of the US Department of Land and Natural Resources and the Pacific Biosciences Research Center at the University of Hawai‘i at Mānoa, and Michael Hadfield, also of the Pacific Biosciences Research Center at the University of Hawai‘i at Mānoa, published a paper in the Biological Journal of the Linnean Society, which described the results of a generic study of Partula gibba, which concluded that the population of this Snail on Rota Island is in fact genetically distinct, and represents a new, cryptic species which had not previously been identified.

Map of the Mariana Islands. Islands where partulids were sampled are indicated by stars. Sischo & Hadfield (2017).

In a second paper, published in the journal ZooKeys on 17 May 2021, David Sischo and Michael Hadfield formerly describe the new Tree Snail species as Partula lutaensis, which combines 'Luta', the indigenous Chamorro name for the island of Rota, and the suffix '-ensis' implies coming from.

The shell of Partula lutaensis is dextral, moderately thin, ovate-to-conic, and slightly perforate. The umbilicus is open, the whorls are moderately convex, and the suture is adpressed. The aperture is ovate-to-elongate, and slightly oblique. The outer lip is reflexed, thick, and glossy, the parietal lip glossy with light or dark colouration. The colour of embryonic the whorls and post-embryonic whorls is variable from shades of brown, buff, white and yellow with a prominent white subsutural band. The 48 specimens measured had an average height of 15.98 mm, and an average width of 10.64 mm.

(Left) Colour morphs of Partula lutaensis found within a 10 × 10-meter quadrat. (Right) Closeup of a Partula lutaensis with a dark shell. Sischo & Hadfield (2021).

All of the known specimens of Partula lutaensis were collected from two species of Plant, the Devil's Ivy, Epiprenmum aureum, and the Halberd Fern, Tectaria crenata. The species is currently present at fairly high densities on Rota Island, however other species of Partulid Snails in the Mariana Archipelago have gone from relative abundance to near-or-actual extinction in very short periods of time, largely due to the activities of introduced predators; a pattern that has been repeated on islands across the Pacific. Particularly troublesome for Partulid Snails are North American carnivorous Snail species in the genus Euglandina, and the New Guinea Flatworm, Platydemus manokwari. On Rota Island Platydemus manokwari has been observed predating Partula lutaensis, suggesting that this species is at risk. Partula gibba, the species to which these Snails were formerly assigned, is protected by a federal Endangered Species declaration, but this will not automatically transfer to the new species, for which reason Sischo and Hadfield consider it imperative that Partula lutaensis be listed as Endangered as soon as possible.

A Partula lutaensis freshly depredated by Platydemus manokwari observed on Rota. Sischo & Hadfield (2021).

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Iceberg the size of Majorca calves from the western side of the Ronne Ice Shelf, Antarctica.

An enormous iceberg has calved from the western side of the Ronne Ice Shelf, Antarctica, according to a press release issued by the British Antarctic Survey on Friday 21 May 2021. The iceberg, newly named A-76, measures around 4320 km², and is floating in the Weddell Sea, currently making it the largest iceberg in the world. The calving is considered a natural event and not attributed to climate warming.

Iceberg A-76, which calved from the Ronne Ice Shelf, Antarctica, in May 2021. European Space Agency/Copernicus Sentinel 1.

The ‘megaberg’ was spotted by British Antarctic Survey researchers in recent images captured by the Copernicus Sentinel-1 mission on the Polar View portal. The iceberg is around 170 km in length and 25 km wide, and is slightly larger than the Spanish island of Majorca or the UK county of Somerset.

The enormity of the iceberg makes it the largest in the world, taking first place from the A-23A iceberg (approximately 3880 km² in size) which is also located in the Weddell Sea. In comparison, the A-74 iceberg that broke off the Brunt Ice Shelf, near Halley Reseach Station in February earlier this year, was only 1270 km².

The iceberg was confirmed by the US National Ice Center using Copernicus Sentinel-1 imagery. The Sentinel-1 mission consists of two polar-orbiting satellites that rely on C-band synthetic aperture radar imaging, returning data regardless of whether it is day or night, allowing year-round viewing of remote regions like Antarctica.

Icebergs are traditionally named from the Antarctic quadrant in which they were originally sighted, then a sequential number, then, if the iceberg breaks, a sequential letter.

Kaitlin Naughten, an ocean modeller at the British Antarctic Survey, explained 'Calving is an essential way for ice shelves to stay in balance. Large calving events only occur occasionally, and they can be very dramatic, but they are not necessarily a sign that the system is changing. There is currently no evidence that the Ronne Ice Shelf is calving more often as a result of climate change.'

According to Alex Brisbourne, a glaciologist at the British Antarctic Survey, who has worked on the Ronne Ice Shelf, 'Iceberg A76 is huge, about the size of the county of Somerset in the UK. It wouldn’t make the top 10 list of the biggest known icebergs of all time though. This calving is part of the natural cycle of the Ronne Ice Shelf. The ice shelf is constantly being fed ice from the Antarctic continent, and eventually chunks break off the ice shelf in this way, forming these big flat icebergs and maintaining a balance. Because they are already floating, as they melt, icebergs do not contribute to sea level rise in a significant way. They have been known to eventually get stuck in places like South Georgia in the South Atlantic, disrupting the feeding of Seals and Penguins.'

'We know that the ocean around Antarctica is warming as a result of global heating but the Weddell Sea, where iceberg A76 sits, is not currently experiencing this warming. Elsewhere around the Antarctic continent however, the warming ocean is melting other ice shelves and this is allowing the ice to drain more quickly off the continent, increasing the rate of sea level rise. Of course, this sea level rise isn’t restricted to Antarctica, it affects sea level around the world, including here in the UK, increasing the frequency and severity of storm surges and coastal flooding.'

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Sunday 23 May 2021

Magnitude 7.3 Earthquake in Qinghai Province, China.

The United States Geological Survey recorded a Magnitude 7.3 Earthquake at a depth of 10.0 km, in southern Qinghai Province, China, slightly before 2.05 am local time on Saturday 22 May 2021 (slightly before 6.05 pm on Friday 21 May, GMT). The event is reported to have led to the collapse of two bridges and damage to numerous buildings, with five people injured and several thousand to temporarily evacuate their homes. 

The approximate location of the 22 May 2021 Qinghai Earthquake. Google Maps.

Qinghai Province lies on the northeast of the Tibetan Plateau, a vast upland created by the impact of India and Eurasia; Earthquake on the Tibetan Plateau is due to the impact of India into Eurasia to the south. The Indian Plate is moving northwards at a rate of 5 cm per year, causing it to impact into Eurasia, which is also moving northward, but only at a rate of 2 cm per year. The collision of the Indian and Eurasian plates has lead to the formation of the Himalayan Mountains, the Tibetan Plateau, and the mountains of southwest China, Central Asia and the Hindu Kush. The 32 highest mountains in the world are on the Plateau (the 33rd, Tirich Mir, is in the nearby Hindu Kush, Afghanistan). India is still moving northwards, but Eurasia is unable to do the same, resulting in an unusual degree of folding and uplift. This has resulted in a number of faults running east-west across the plateau, with sections being forced eastward into China.

Collapsed bridges in Qinghai Province, China, following a Magnitude 7.3 Earthquake on 22 May 2021. China Central Television.
Block diagram showing how the impact of the Indian Plate into Eurasia is causing uplift on the Tibetan Plateau. Jayne Doucette/Woods Hole Oceanographic Institution.

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Helarctos malayanus: Understanding the impact of Palm Oil plantations around the Tabin Wildlife Reserve on Malayan Sun Bears

Wildlife reserves around the world are coming under increasing pressure due to rising Humans populations and activities in adjacent areas. Originally conceived as refuges in which the core habitats of threatened species would be preserved, surrounded by buffers of limited activity, many of these reserves now have intensive Human activities extending directly to their boundaries, provoking a rise in Human-wildlife activities, both as Humans enter parks to hunt or extract Plant or mineral resources, and as Animals on the boundaries of parks try to take advantage of Human resources, by crop raiding or hunting livestock.

Populations of Animals in parks are therefore becoming particularly prone to edge effects, with Animals populations living close to reserve boundaries particularly prone to extinction. This is particularly true for Animals living on smaller reserves, and large carnivorous Animals, which require larger territories and are more vulnerable to Human-wildlife contacts.

Wildlife in Southeast Asia is increasingly vulnerable to a range of anthropogenic threats, driven largely by deforestation. More than 50% of tropical forests in Southeast Asia have been felled for agriculture and other commercial purposes. As well as the direct loss of habitat, many wildlife populations have become more vulnerable to hunting, as new road networks open up formerly remote areas. This hunting is driven both by the desire to obtain bushmeat for local consumption, and the international wildlife trade, in which both whole Animals and Animal body parts are traded over long distances across international boundaries.

Sun Bears, Helarctos malayanus, are hunted for their paws and gall bladders, which have high commercial values on the international market. The species is found in the evergreen forests of the Sundaland sub-region and the seasonal forests of mainland Southeast Asia. Sun Bears are currently classified as Vulnerable under the terms of the International Union for the Conservation of Nature’s Red List of Threatened Species, but their populations are thought to have declined by 30% in the last 30 years, due to a combination of habitat loss and hunting for body parts, making it likely the species will be reclassified as Endangered in the near future.

A Borneo Sun Bear, Helarctos malayanus euryspilus, in Sabah State, Malaysia. Sunbear Survival.

Efforts to set up conservation plans for Sun Bears have been hampered by a lack of information about their distribution, ecology, and population structures, and while some work to improve our understanding of this has been undertaken in recent years, there is still much about the species that is not fully understood. Notably, it was long thought that Sun Bears were restricted to undisturbed primary rainforests, but recent studies have suggested that they are also found to some extent in secondary forests and even areas that have recently been cleared by loggers.

The impact of land-use changes upon vulnerable species has been little studied in Southeast Asia, although, as in other areas, these impacts are likely to be severe when they are close to reserve boundaries, as such encroachments will lead to increased Human-wildlife conflicts, enhanced opportunities for poachers to target wildlife, barriers to the movement of species between remaining areas of habitat, and changes in Animal behaviour in changing environments. In Malaysia there has been a rapid spread of monocultural Oil Palm plantations into many areas previously covered by pristine rainforests, with a subsequent negative impact on wildlife populations. There plantations have a severe impact on Mammal diversity, with the number of species declining rapidly away from areas of natural forests. Nonetheless, many species have found ways to exploit these new environments, and Sub Bears, which are generally diurnal, are known to make nocturnal foraging forays into Oil Palm plantations. Such crop-raiding behaviour gives the Bears access to a highly nutritious food-source, but fuels conflict with villagers and plantation workers. This in turn tends to lead to a rise in poaching, typically by snaring, which leads to boundary areas becoming population sinks, as Bears in these areas are drawn into the plantations to access the new food source, where they become more vulnerable to poaching.

In a paper published in the journal Wildlife Biology on 3 May 2021, Thye Lim Tee of the Department of Biological Sciences at Sunway University, Frank van Manen of the Interagency Grizzly Bear Study Team at the Northern Rocky Mountain Science Center, Petra Kretzschmar of the Department of Evolutionary Ecology at the Leibniz Institute for Zoo and Wildlife Research, Stuart Sharp of the Lancaster Environment Centre at Lancaster University, Siew Te Wong of the Bornean Sun Bear Conservation Centre, Sumbin Gadas of the Sabah Wildlife Department, and Shyamala Ratnayeke, also of the Department of Biological Sciences at Sunway University, present the results of a study which used remote cameras along a gradient across the boundary of the Tabin Wildlife Reserve in Sabah State, Malaysian Borneo, to determine the presence or absence of Sun Bears in landscapes subject to Human alteration.

The Tabin Wildlife Reserve is an area of lowland Dipterocarp rainforest northeast of Lahad Datu. It was created in 1984 for the conservation of the Sumatran Rhinoceros, Dicerorhinus sumatrensis, and now represents the largest contiguous forested area in Sabah, although it is surrounded by Oil Palm plantations. Rainfall in the reserve averages 150–300 cm per year, and temperatures from a mean daily maximum of 32.0°C to a mean daily minimum of 22.0°C.

The Tabin Wildlife Reserve preserves an excellent habitat for forest-dwelling Bornean species, but Oil Palm plantations now extend to its boundaries on almost all sides. Google Maps.

Tee et al. used data from two sources in their study; the first was collected during Sumatran Rhino surveys at Tabin Wildlife Reserve from July 2012 through February 2013, and the second carried out by Thye Lim Tee April–October 2017. Only data from independent camera sites that were located at least 1 km apart was used in the study, with sites that were closer being omitted, resulting in a total of 83 camera sites being included in the study. 

The 2012-13 Rhino surveys were conducted in the central and northern part of Tabin Wildlife Reserve, with cameras placed within 6 km² square grid cells based on a minimum home-range size of Sumatran Rhinos at game trails, mud wallows or hill crests. This study yielded data from 39 cameras with an average distance of 1.7 km. These camaras operated 24 hours a day for an average of 96 days.

During the 2017 study 44 passive infrared remote cameras were deployed along forest trails, the reserve boundary, old logging roads and within the core area of the reserve. These cameras were separated by an average distance of 1.4 km, selected to establish a gradient in relation to landscape features of interest, such as distance to roads and reserve boundary, with cameras placed to optimise Sun Bear detection, and baited with Shrimp paste and pieces of salted Fish placed in black shading net. These cameras were deployed at each site for 28 days, before being moved to a new site, with 13-18 cameras active at any one time.

Tee et al. used a linear model to correlate landscape features with Sun Bear presence, judging Sun Bears as present in an area based upon camera sightings, bait removal, or claw marks on trees. Bears were assessed as being present if they were detected once within the entire period of observation, with no finer differentiation than either present or absent, as the species is somewhat cryptic in its habits, and hard to detect. The presence or absence of Bears was then compared to seven other landscape variables; (1) elevation, (2) terrain ruggedness, (3) distance to nearest road, (4) distance to nearest permanent river, (5) distance to nearest reserve boundary, (6) human density and (7) percentage natural forest cover. The results were mapped in Quantum GIS, using elevation data from the Shuttle Radar Topography Mission, Human density data from the LandScan 2007 global population data set, road data from Google Earth Pro, combined with data obtained by mapping with a Garmin GPSmap 62s Global Positioning Unit, and other data from previous studies carried out in the area. Because Oil Palm plantations extend to the boundaries of the reserve on all sides, all areas outside the reserve were considered to have 0% natural tree cover. Statistical processing was carried out using the R software package.

Distribution of 83 remote camera stations and Sun Bear presence or absence during two remote camera surveys in Tabin Wildlife Reserve, Sabah, Malaysia, 2012–2013 (circles) and 2017 (triangles). Black circles or triangles indicate sites with Sun Bear presence, whereas white circles or triangles indicate sites with no detection of Sun Bears. Tee et al. (2021).

Tee et al. made 164 independent Sun Bear sightings over a total of 4862 study-nights, with Bears being sighted at 47 of the 83 sites included in the study. Distance from road was found to be the most reliable indicator of Human disturbance, as roads effectively run around all the boundaries of the reserve. Bears were found to be most active away from these boundary areas, with 138 of the 164 Bear-detections occurring at 35 of the 51 sites designated as 'core areas', while 26 sightings occurred at 14 of the 32 sites designated as 'boundary areas'. Thus Bears were 3.3 times more likely to be sighted in 'core areas' than 'boundary areas'. Sun Bears were most active at around 7.00 am and 4.00 pm in the core areas, whereas in the boundary areas they were most active between 5.00 am and 6.00 am. 

Predicted relative probability of sun bear presence in Tabin Wildlife Reserve, Sabah, Malaysia, based on remote camera data collected during surveys in 2012–2013 and 2017. Predictions from seven logistic regression models were multiplied by their respective AICc weights and summed to obtain model-averaged probabilities. Model covariates included distance to nearest road, elevation, human density, percent natural forest cover and survey. For models that included the survey covariate, we averaged predicted values for the two equations representing each of the two survey periods. Tee et al. (2021).

Sun Bears were found to be most present in areas away from roads, at higher elevations, and with lower percentages of natural forest cover. However, the degree of elevation present in the Tabin Wildlife Reserve is limited, with the highest parts, in the centre of the park, only reaching 571 m above sealevel, and the elevation falling to 20-100 m at the reserve's boundaries. Higher elevation was also closely correlated with terrain ruggedness, although the correlation between Bear-presence and terrain ruggedness, was much lower than that for elevation. Tee et al. suspect that the correlation between Bear-presence and elevation may actually reflect some variable not measured in their study. In particular they note that the flora of low-lying areas within the reserve is relatively uniform, but that tropical forest floras often vary considerably with even small changes in elevation, which may suggest that the Bears may be responding to the availability of some resource, such as food or cover. Bears were also found to be found in areas with lower levels of natural cover, although this measure appeared to have been skewed by the activities of Bears in the boundary areas, with those Bears detected here being predominantly detected close to the boundaries with Oil Palm plantations, 

Tee et al. had a higher detection rate for Sun Bears than previous studies carried out at other reserves in Sabah. This was particularly notable for the baited sites, but also true of the sites from the 2012-13 Rhino survey, which Tee et al. take to indicate that Sun Bears are present at higher densities in the Tabin Wildlife Reserve than in other reserves in Sabah, which in turn probably relates to the size of the reserve, which preserves a larger fragment of forest that any other reserve on Sabah, all of which are impacted by the spread of Oil Palm plantations. 

The greater activity of Sun Bears during twilight hours in boundary areas of the reserve is almost certainly an indicator of crop-raiding activities by these Bears, with previous studies having indicated that such crop-raiding is almost exclusively nocturnal, with Bears returning in the forests during the day. Bears appeared only to venture close to roads in areas where this was associated with access to Oil Palm plantations, with Bears generally avoiding roads in the interior of the reserve. 

Overall, Tee et al.'s findings are consistent with previous studies, which have found that Human activities, and in particular the spread of Oil Palm plantations, have had a strong negative impact upon the lives of Sun Bears, and that the species will tend to prioritise avoiding contact with Humans above all other activities, including foraging for food.

Studies of other Bear species have detected a similar aversion to roads, with Sloth Bears, Melursus ursinus, in Sri Lanka, having been shown to avoid areas with roads completely, and Brown Bears, Ursus arctos, avoiding roads with high traffic levels and Human settlements in general. Bears are intelligent Animals, and can modify their behaviour to accommodate Human activities, but the presence of roads is strongly associated with rises in Bear-poaching and other forms of Human-Bear conflict, which have a negative impact on Bear populations. This is of particular importance for the Tabin Wildlife Reserve, where there is no control on access from roads abutting the reserve, nor any form of anti-poaching precautions in place. Poaching in the area is known to be highly profitable, with poachers targeting both protected Animals and Plants (such as the Agarwood Tree, Aquilaria spp.). Tee et al. photographed groups of armed poachers within the reserve on three occasions, all within 1 km of a plantation road. 

Malaysia is the world's second largest producer of Palm Oil, and Sabah produces about 27% of the country's total output. Unsurprisingly, Sabah is also a global deforestation hotspot, with 15 000 km² of Oil Palm plantations, out of a total land area of 74 000 km². This expansion of Oil Palm plantations has been accompanied by an expansion of the infrastructure which supports such activities, most notably roads. In an area such as the Tabin Wildlife Reserve, which is surrounded by plantations and roads on almost all sides, simple passive protection of species such as Sun Bears (i.e. declaring these species to be protected and hoping people will comply with this) is unlikely to be effective, and a more robust species protection plan will need to be put into place if these Animals are not to go extinct. Any such species protection plan needs to be built upon studies of hunting and poaching in the area, and the responses of Bears to Human activities, and include rigorous anti-poaching measures and formal partnerships between locally-based non-governmental organisations, local ecotourism resorts, plantation stakeholders and local communities.

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