mammals
laelaps | April 25, 2010
A family of North American river otters (Lontra canadensis), photographed in Yellowstone National Park.
laelaps | April 22, 2010
A Madagascar sucker-footed bat (Myzopoda aurita).
In the tropical forests of Madagascar, there lives a very peculiar kind of bat. While most bats roost by hanging upside-down from cave ceilings or tree branches, the Madagascar sucker-footed bat (Myzopoda aurita) holds itself head-up thanks to a set of adhesive pads on its wings. Nor is it the only bat to do so. Thousands of miles away in the jungles of Central and South America, Spix's disk-winged bat (Thyroptera tricolor) does the same thing, but how do their sucker pads work, and why do they choose to roost in a different way from all…
laelaps | April 21, 2010
In a clip from the recent BBC program Museum of Life, visitors to London's Natural History Museum try to identify what kind of animal Megatherium was. Paleo fans will know it as one of the largest ground sloths to have ever lived (as well as one of the first to be described), but if I didn't know that and had no background in paleo, I might think it was a dinosaur, too!
jgoldman | April 21, 2010Animals dream, too!
It's definitely not a seizure, and it's definitely not random motor actions. Those actions are totally coordinated. Poor dog must have been dreaming about a dog fight or something.
laelaps | April 20, 2010
For much of the past 130 million years South America was an island continent, and on it organisms evolved in "splendid isolation." Mammals, especially, evolved into forms not seen anywhere else, and while some mammalian immigrants made their way to South America during the past 30 million years it was not until about three million years ago, with the closing of the isthmus of Panama, that large animals from North and South America began to wander across the new landbridge and mix with the endemic faunas. This is why there were elephants in South America and giant ground sloths in North…
laelaps | April 19, 2010
Two giant anteaters fight it out. On the left, the individuals lash out at each other with their enormous claws, and on the right they posture at each other (with the dominant animal, with the upright and puffed-out tail, on the right). From Kruetz et al 2009.
In the northern state of Roraima in Brazil, small plantations of the black wattle tree (Acacia mangium) serve up plenty of food to carpenter ants and other insects, and the variety of six-legged pests has attracted numerous giant anteaters. The trouble is that these immense xenarthrans don't typically get along very well.
As…
laelaps | April 17, 2010
What kind of social-insect-eating mammal is stranger than a numbat? Well, a pangolin, for one. From The Life of Mammals.
For more on the pangolin's prey, check out one of the newest additions to the ScienceBlogs family, Myrmecos.
laelaps | April 13, 2010
A red panda (Ailurus fulgens, left, photographed at the Bronx Zoo) and a giant panda (Ailuropoda melanoleuca, right, photographed at the National Zoo).
As the paleontologist Stephen Jay Gould observed in one of his most famous essays, the thumbs of giant pandas (Ailuropoda melanoleuca) are nothing at all like the large digits on our own hands. Their accessory "thumbs", visible on the surface as a differentiated part of the pad on the "palm" of the hand, are modified sesamoid bones derived from the wrist. They are jury-rigged bits of anatomy which cast nature as an "excellent tinkerer, not…
laelaps | April 13, 2010
A sloth bear (Melursus ursinus), photographed at the National Zoo in Washington DC.
laelaps | April 12, 2010
An African wild dog (Lycaon pictus, left) compared to a spotted hyena (Crocuta crocuta, right). Both photographed at the Bronx Zoo.
It never fails. Whenever I visit a zoo's African wild dog exhibit someone inevitably asks "Are those hyenas?", and when I visit spotted hyena enclosures I often hear the question "Are those dogs?" These carnivores, known to scientists as Lycaon pictus and Crocuta crocuta (respectively), are only distant cousins, but the vague similarities shared between them often cause people to confuse one with the other.
There are a few quick and dirty ways to tell them…
jgoldman | April 12, 2010The party isn't over yet! Here's another helping of Monday Pets. Enjoy!
Wild Dog crawled into the Cave and laid his head on the Woman's lap... And the Woman said, "His name is not Wild Dog any more, but the First Friend."
--Just So Stories, Rudyard Kipling.
Archaeological evidence indicates that dogs were already a part of human society around the end of the Ice Age. Small dog skeletons have been unearthed in human communities as far back as 6- to 12-thousand years ago in Europe, the Middle East, and China. The jawbone of a domestic dog was found in a late Paleolithic grave in Germany, and…
jgoldman | April 12, 2010The party continues! Today you get a double-dose of Monday Pets. Here's one from the archives. Later today, you can expect a new one.
I often write about animals that the average person does not interact with all that much on a day-to-day basis. Today, I introduce something I like to call "Monday Pets". The focus of Monday Pets will be the animals that we intentionally bring into our lives as pets. Sometimes those animals are even considered part of the family. Ever notice some weird behavior that you notice your pets doing? Want to know more about it? Email me. Always wanted to know if your…
laelaps | April 11, 2010
If you're going to have termites for lunch, you'll need the right kind of equipment. From The Life of Mammals.
laelaps | April 8, 2010
A diagram of how the skeletons of Australopithecus sediba came to be preserved in the Malapa cave deposit. From Dirks et al, 2010.
A little less than two million years ago, in what is now South Africa, a torrential downpour washed the bodies of two humans into the deep recesses of a cave. Just how their remains came to be in the cave in the first place is a mystery. Perhaps they fell in through the gaping hole in the cave roof just as hyenas, saber-toothed cats, horses, and other animals had, but, however the humans entered the cave, their bones ultimately came to rest in a natural bowl…
laelaps | April 7, 2010
A leopard (Panthera pardus). Image from Wikipedia.
When a leopard eats a baboon, what is left behind? This question is not only relevant to primatologists and zoologists. Even though instances of predation on humans is relatively rare, big cats still kill and consume people, and when they do they can virtually obliterate a body. Yet, just like a human criminal, the dining habits of big cats leave tell-tale clues, and in 2004 researchers Travis Pickering and Kristian Carlson fed two captive leopards eight complete baboon carcasses each in order catalog the most useful ways to identify the…
laelaps | April 7, 2010Want the dirt on the new species of fossil human which will be described in Science this week? Tune in to the BBC World Service "Science in Action" program this Friday to hear me discuss the discovery with host Jon Stewart. The program should be available on the web sometime after it airs, as well.
laelaps | April 6, 2010
A leopard (Panthera pardus). Image from Wikipedia.
SK-54 is a curious fossil. The 1.5 million year old skullcap represents a juvenile Paranthropus robustus, one of the heavy-jawed hominins which lived in prehistoric South Africa, but there is something that makes this skull fragment particularly special. Near one of the sutures along the back of the skull are two neat puncture marks, the hallmark of a leopard.
Even though it was initially proposed that SK-54 had been murdered by another australopithecine wielding a weapon of bone or horn, in the late 1960's the paleontologist C.K. Brain…