Звери самые маленькие, 1927. Illustrated by Vasily Vatagin.
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Звери самые маленькие, 1927. Illustrated by Vasily Vatagin.
source
A pygmy marmoset sitting on a bunch of green bananas.
A fun fact about urban marmosets is that, due to a presence of both common (Callithrix jacchus) and black tufted marmosets (Callithrix penicillata) in cities and both species belonging to the genus Callithrix, it’s not uncommon to see naturally occurring* hybrids between the two!
Pictures by taguatu_guassu and sebastianlescano on iNaturalist
They usually look more closely like common marmosets (left) but with darker darker tufts of hair on their ears like black-tufted marmosets (right)!
Luis Xertu (Mexican, 1985) - Marmosets on a Tree (2025)
pygmy marmoset?
Sure, I'll do the whole genus!
Have you seen a pygmy marmoset (Genus: Cebuella)?
I have now
Yes, in photos/videos
Yes, irl
I'm not sure
There are two species of pygmy marmoset, the Western pygmy marmoset and the Eastern pygmy marmoset.
A common marmoset (Callithrix jacchus) in Yorkshire Wildlife Park, UK
by John K Perry
Monkeys’ Business
Just like people, monkeys behave in an infinite number of unpredictable ways. But essential health research relies on testing the impact of treatments for neuropsychiatric diseases like autism or depression on animals before giving them to vulnerable people. Therefore, establishing regular patterns of behaviour in both healthy animals and those which are genetically engineered to represent a model for particular conditions is essential to observe whether treatments can restore normal behaviour. A new study quantified the movement of a large dataset of marmosets in normal circumstances (start–0:17 in the video) and in response to stimuli such as food (0:17–end) or new cage mates. With behavioural biomarkers set, it will be possible to test treatments for efficacy in a range of animal models, to be sure of their safety and impact before bringing medicines to patients.
Written by Anthony Lewis
Video from work by William Menegas and Erin Corbett, and colleagues: adapted to double speed
Hock E. Tan and K. Lisa Yang Center for Autism Research, Yang Tan Collective, McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
Video provided by and copyright held by the original authors
Published in eLife (reviewed preprint), December 2024
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Edward Landseer (1802-1873), 'The Marmosets', ''St. Nicholas'', Vol. 2, #5, 1875 Source