Kai Caspar

@nomascus.bsky.social

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Zoology lecturer @hhu.de | Armchair biologist | Focus on rodents underground and gibbons in the trees, also one of @themanybirds.bsky.social | Organismic vertebrate biology | Views my own

Graphical abstract from the paper showing the apparatus used to examine tool use learning in hornbills
Model from the Perea-Garcia et al. study wearing a dark lens to mimic chimp-like eyes on the left and her natural eyes on the right (note that different from chimps, the model has a grey iris color).
Zoo sign for camels, resembling an extinct South American ungulate
Skeleton of a Ganges River dolphin and model of an Amazon River dolphin in the Prague Natural History Museum (both relevant to work presented at the DGS meeting)
Grey figurines of Deinotherium and Nothritheriops
Figure from preprint showing that peri-iridal brightness is negatively correlated with eye size.
Figure from https://onlinelibrary.wiley.com/doi/10.1111/brv.70033: Eye appearance of primates originating from different latitudes
Phylogenetic tree of 62 terrestrial mammals from the preprint. Bar length indicates eye size, bar color approximates brightness of peri-iridal tissues.
Cover photo, showing portraits of Stan Braude and impressions of various mole-rat species
Photo of a male blind mole-rat of the newly described species on a meadow. Photo by Oleg V. Brandler
The original fossil of Eurotamandua from the Messel exhibition at the Darmstadt Natural History Museum.
3D-printed endocast of a hummingbird inner ear with tiny hummingbird toy figure on the right
Bird skeletons in a museum collection. Cassowary in focus.
Fukomys mole-rats huddling
Ansell's mole-rat, held by a human. Loose skin on the back is obvious. Photo by Sarah M. Wilms.
Plot showing size distribution of hyaluronan molecules in the skin o Ansell's mole-rat (AMR), naked mole-rat (NMR) and guinea pig (GP).
Maximum stress the skin can endure in a number of rodent taxa. The naked mole-rat is an outlier, combining high resilience with thin skin.
Cutometric comparison of subterranean (blue) and surface-dwelling (red) rodent taxa. The higher R8, the greater the skin's ability to recover its initial conformation (elasticity).
Group of Ansell's mole-rats huddling
Scatter plot with eye sight acuity (measured in cycles per degree) on the y-axis and eye diameter (in mm) on the x-axis. Birds tend to have higher acuity than mammals at a given eyesight, except anthropoid primates (monkeys and apes) that outperform most birds, except for a few raptors. Some birds of prey (falcons, eagles) exhibit the highest recorded acuity. Corvids cluster between other birds and anthropoids, showing higher acuity than would be expected.
Kenyan naked mole-rat (Heterocephalus ansorgei) in a lab.
Macrauchenia from Prehistoric Planet 3
Photo of a common wombat walking through the autumn leaf litter
Photo of a NatGeo article on gibbon dance, discussing the study by Coye et al. Female Nomascus leucogenys is shown, photographed by Joel Sartore
Kagu, duetting
Photo of the front of Prague's National Museum with an Australopithecus banner
Picture of a copy of "Bird Brains and Behavior" by Striedter & Iwaniuk: https://mitpress.mit.edu/9780262552738/bird-brains-and-behavior/
Close-up of eyes and nose of a Bornean orangutan
Colobus monkey (Colobus guereza) approaching a two-choice set up to test for its ability to infer the hiding location of a bait by exclusion.
CT renders of the brains and trigeminal nerves of iodine-stained tenrec specimens. Taken from Sulser & MCPhee (2025): https://www.nature.com/articles/s42003-025-08489-8
Phylogenetic tree of birds, with orders placed essentially at random.
Murals and reliefs showing Ichthyosaurus, Stegosaurus, Pteranodon, Triceratops, Edaphosaurus and Claosaurus
Low-latitude primates (incl. humans) have darker peri-iridal tissues, probably an adaptation to counter damaging UV radiation. Figure from Perea-García et al. (2025)
Phylogenetic tree of anthropoid primates, illustrating the diversity of peri-iridal pigmentation. From Perea-García et al. (2025)
Chimp gazing afar.
Figure from Perea-Garcia et al. (2025) - eyes of diverse humans, showing a spectrum of peri-iridal pigmentations. Photos were taken my Marios Forsos, Juan Perea-García, and Gunther Deichmann.
Figure from Perea-García et al. (2025) comparing peri-iridal brightness in humans, Southern pig-tailed macaques, and Golden langurs
Human eye on top, squirrel monkey eye below. Little of the peri-iridal tissues are exposed in the squirrel monkey, which is now understood to derive from simply scaling constraints and human adaptations to horizontal scanning. There is no evidence for social cognition being tied to such differences in eye appearances.
Carboniferous deposits at Piesberg, Osnabrück,
Drawing of the extict sperm whale Eophyseter engaging in aerial urination. Art by Joshua Knüppe.
Wild Amazon River dolphin showing vibrissae on both the upper and lower jaw. Photo by Nortondefeis, CC BY-SA 4.0
Wild Amazon river dolphin raising its head out of the water and facing the camera with an open mouth.
Random photos of mole-rats from the last 6 years
Pair of steamer ducks
Male okapi
E-Mails from fake journals soliciting manuscripts on gibbon dance
Embarassing AI art of "Ankylosaurus". Says its body was covered in plates
Line drawings of river dolphins interacting with various human-made objects like brushes and bins
AI-generated hybrid creature with a rodent head and a quoll-like body, sitting on a rock at night time.
Fossil of Pholidocercus hassiacus, an early relative of hedgehogs and shrews. The fossil preserves the tail, which is covered in horn plates, and impressions of the fur. Hairs on the back resembled spines, though less rigid than those of modern hedgehogs. Photo by Oilshale.
A young naked mole-rat on a lab bench
Fig. 3 from Yuan et al., showing 3D reconstructions of myosoricine shrews with more or less elongated neck sesamoids.
Sign inviting you to join the talk "Watch that scene - gibbon the dancing queen - rhythmic displays in small apes" at Toruń University, 12.12.24, 12:00.
Life reconstruction of Terastiodontosaurus by Jaime Chirinos preying on a land snail. The worm lizard is depicted similarly to extant Amphisbaena alba.
Current Hatzegopteryx model in the Karlsruhe Museum
Logo of the conference on a banner
Phylogenetic tree of the 136 studied avian species with neophobia scores mapped onto it.