Can you see that monkey up there?

by Greg Mayer Among the first phenomena to be interpreted in a Darwinian manner after the publication of the Origin of Species was adaptive coloration, most famously Batesian mimicry (wherein a palatable organism mimics a noxious organism); Jerry has recently posted  on mimicry in insects and in birds. Matthew has brought to our attention a […]

Caturday felid– No.3, the snow leopard

by Greg Mayer As an extra bonus felid for today, and continuing the theme of cat coat patterns as camouflage, here’s the snow leopard (Panthera uncia). You can’t see the snow leopard or it’s pattern very well, but, of course, that’s the point. Its head is to the right. (BTW, is anyone getting the Monty […]

The evolution of cat coat patterns

Why are some species of kittehs plain, while others have spots, stripes, or more elaborate patterns? A provisional answer comes from a new paper by William Allen et al., “Why the leopard got his spots: relating pattern development to ecology in felids”, in the Proceedings of the Royal Society.  The paper’s title, of course, comes […]

Caturday Felid- spotted lions

by Greg Mayer Spotted lions, semi-mythical beasts and the subject of cryptozoological inquiry, have been discussed here at WEIT before, but the spotted lions here are not mythical at all, because they are cubs. Lion cubs, as we’ve also discussed before here at WEIT, are born spotted, and retain some spots for up to two […]

Albino squirrel update

by Greg Mayer Observant reader Chris Helzer saw an albino squirrel outside the National Museum of Natural History a few days after I did, and got a much better picture of it, which he has kindly allowed me to post here. This is probably the same squirrel I saw, and it seems to be on […]

Caturday felid: the King Cheetah

by Greg Mayer Of interest to both ecological geneticists studying vertebrate polymorphisms and cryptozoologists is the king cheetah. The king cheetah, known only from southern Africa, is a striking pattern variation of the common cheetah (Acinonyx jubatus). Instead of being spotted, the dark markings of the king cheetah coalesce into stripes and vermiculations, especially along […]

Polymorphism in vertebrates

by Greg Mayer Darwin’s theory of evolution (and ours), unlike that of Lamarck, is variational, rather than transformational: the process of evolution is a change in frequency of different variants within a population, not a transformation of the individuals.  Darwin thus made the origin, nature, and inheritance of variation key problems for biology; indeed, for […]

Caturday felid: the Spotted Lion

by Greg Mayer One of the most enigmatic of the felids is the spotted lion. Indeed, it’s so enigmatic that it might, in some senses, be said to not even exist. As you may recall from Jerry’s earlier posting of a video of lion cubs, lions are born with spots, which disappear as they mature. […]

Poison dart frogs: poison, yes; dart, not so much

by Greg Mayer The brightly colored, poisonous frogs of the family Dendrobatidae are usually called poison dart frogs, but the name is a bit of a misnomer. While they do have toxic alkaloids in their skins, only three species are definitely known to be used for poisoning blowgun darts– Phyllobates aurotaenia, Phyllobates bicolor, and Phyllobates […]

Rational exuberance

by Greg Mayer Continuing with the frog theme, here are two representatives of Dendrobates pumilio, the strawberry poison dart frog, from Costa Rica. As the word “poison” in their vernacular name indicates, these frogs are toxic, and their bright coloration is aposematic: it advertises the toxicity of the frog, and protects them from predators. They […]