Modern forensic science typically involves the detailed examination
of corpses where foul play is suspected, with the aim of identifying any marks
on the body, and relating them to the cause of, and circumstances surrounding,
the death of the person in question. Numerous Arthropods are known to feed on
vertebrate carrion, including Human remains, and marks left by feeding
Arthropods have in the past been mistaken for burns, evidence of intravenous
drug use, bite marks, defensive wounds and a variety of other forms of
evidence. As such forensic scientists in a number of areas have begun to
experiment with Human remains left to decompose in the environment, in order to
better understand how Arthropod feeding traces and other forms of environmental
destruction affect a body after death.
In a paper published in the Journal of Medical Entomology in January
2015, a team of scientists led by Jennifer Pechal of the Department of Biology
at the University of Dayton and the Department of Entomology at Michigan State University, discuss the results of an experiment in which a body was left
exposed at the Forensic Anthropology Center at Texas State University, and subsequently
targeted by a variety of Arthropods not previously associated with the
consumption of Human remains.
Firstly the cadaver was targeted by a gravid female Katydid, Pediodectes haldemani, which began
feeding on the lower right arm of the body, approximately 32 hours after it was
placed in the field. Katydids, Tettigoniidae, are Orthopteran Insects related
to Grasshoppers and Crickets, but unlike these plant-eating groups they are
generally omnivorous in their dietary preferences, and the species Pediodectes haldemani is known to be
almost totally carnivorous. While Katydid have previously been recorded
consuming vertebrate carrion, this is the first recorded instance of the
consumption of Human remains by a Katydid, and Pechal et al. suggest that this might be slightly atypical behaviour,
fuelled by a need for extra protein in the gravid female.
A gravid, female Pediodectes haldemani
(Orthoptera: Tettigoniidae) feeding on the right forearm of a set of human
remains (top), and the resulting physical artifact (indicated by the black
arrow) on the remains by the feeding Pediodectes haldemani
(bottom). Pechal et al. (2015).
Secondly the remains were visited by a Common Woodlouse, Armadillidium cf. vulgare, this time feeding on the lower left arm. Woodlice are
terrestrial Isopod Crustaceans, with a typicalldetritivorous diet; they are
most commonly associated with plant remains, but are known to eat carrion,
though once again this is the first time that a Woodlouse has been recorded
eating Human remains.
Armadillidium cf. vulgare (Isopoda:
Armadilidiidae) feeding on the left forearm of a human set of remains (top),
and the resulting artifact (indicated by theblack arrow) on the remains from
the isopod activity (bottom). Pechal et al. (2015).
Finally the body was visited by a colony of Red Fire Ants, Solenopsis invicta, an imported species
in the US, but which has become common in grasslands; Ants, including Red Fire
Ants, are common visitors to carrion. On this occasion it is unclear whether
the Ants actually fed on the remains, rather they entered the body via the hole
left by the Katydid’s feeding and appeared to build a shelter there, using soil
and small pieces of woody debris, a structure which would have been difficult
to interpret had its construction not been observed.
A structure consisting of soil, small organic woody
debris, and other organic material by red imported Fire Ants, Solenopsis invicta (Hymenoptera:
Formicidae), in the artifact resulting from Pediodectes haldemani feeding
activity on the leftforearm of the descendent. The structure was re-constructed
each time the remains were disturbed for sampling purposes. The small dots
surrounding the debris pile are fly artifacts or speck. Pechal et al. (2015).
See also…
Two new species of Katydids from Pakistan. Katydids (or Buschcrickets), Tettigonioidea, are Members of the
Insect Order Orthoptera, which also includes Crickets and Grasshoppers. They
are...
The impact of the Yellow Crazy Ant on the Vallée de Mai Palm Forest of Praslin Island. Ants are often highly adaptable animals, and many species have
proven to be highly invasive pests, able to reach new homes by hitching a ride
on cargo moved by Humans, and often proceeding modify the ...
Three new species of Katydid from China. Katydids of the genus Xizicusand its close relatives are found across eastern Asia, though the taxonomy of
the group is currently somewhat confused, in part due to publications being
published in different languages...
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