mammals
laelaps | July 13, 2009
Hippopotamus amphibius, photographed at the Philadelphia Zoo.
Have you ever tried to walk along the bottom of a pool while fully submerged? It isn't easy. Keeping your feet on the bottom is enough of a task, and you would probably need a weight belt to take an underwater stroll. Hippos (Hippopotamus amphibius), though, walk and even prance along the bottom of lakes and rivers with ease. How do they do it?
When compared to a whale or even a manatee (the latter of which I will address a bit later on) a hippo does not look especially well-adapted to life in the water. It has a low, squat…
edyong | July 13, 2009While dogs can often be taught new tricks, cat-owners will be all too aware that it can be very difficult to persuade them to do something they don't want to do. Eddie Izzard summed it up best in his legendary Pavlov's cat sketch, where felines are quite capable of outfoxing (outcatting?) eminent Welsh-Russian psychologists. Real cats may be less devious, but only just - new research suggests that they are very skilled at getting their human owners to do their bidding.
When they want food, domestic cats will often purr in a strangely plaintive way that their owners find difficult to ignore…
grrlscientist | July 13, 2009tags: Antarctica, Orcas, Killer Whales, Orcinus orca, wildlife, streaming video
In this video, we are given a look at a pod of Orcas -- "killer whales" -- Orcinus orca, that live in the Antarctic. I have spent many happy hours in Friday Harbor at the University of Washington's research station, watching Orcas and talking to the biologists who study them. These biologists were fairly certain that the Friday harbor Orcas are a different subspecies or species from those orcas that live in more open waters, such as the ones you see in this video. The reasons? At the time, they didn't have DNA…
laelaps | July 8, 2009
A beautiful artistic reconstruction of Indohyus by Carl Buell.
During the last 30 years paleontologists have uncovered a startling amount of fossil evidence which has illuminated the early evolution of whales. The earliest members of the cetacea looked nothing like the marine mammals we are familiar with today, and in December of 2007 a paper in Nature identified a small hoofed mammal called Indohyus as one of the closest relatives to the earliest whales. This hypothesis was supported by a subsequent study published a few months ago in the same journal.
One of the most interesting aspects…
laelaps | July 7, 2009
Parts of the skull, including the upper jaws (maxillae), of Eritherium azzouzorum as seen from the front (top) and below (bottom). From Gheerbrant (2009).
Yesterday I blogged about the ~27 million year old elephantimorph Eritreum, a creature that stood only about four feet high at the shoulder, but there were once even smaller proboscideans. About sixty million years ago in what is now Morocco there lived a rabbit-sized (~5 kg) hoofed mammal that is one of the earliest known relatives of the modern behemoths of Africa and Asia. Called Eritherium azzouzorum, it was a small mammal that…
laelaps | July 6, 2009
A restoration of Eritreum compared to the larger Gomphotherium. From Shoshani et al. (2009).
Before I loved dinosaurs, I loved elephants. I would run around the backyard with my little pith helmet on, firing my "elephant mover" to herd the imaginary pachyderms. (At the time I did not understand what guns did. When they went off in the documentaries I saw that the elephants moved, therefore guns were "elephant movers.") It would only be much later, when I could properly appreciate the stout bones I saw in the halls of the American Museum of Natural History, that I would more fully…
laelaps | July 6, 2009
An Eastern grey squirrel (Sciurus carolinensis), photographed at the Central Park Zoo.
laelaps | July 2, 2009
A pair of clouded leopard cubs born in Smithsonian National Zoo facilities just a few months ago, via NPR.
edyong | July 2, 2009The island of Hirta, on the western coast of Scotland, is home to a special breed of sheep. Soay sheep, named after a neighbouring island, are the most primitive breed of domestic sheep and have lived on the isles of St Kilda for at least a millennium. They're generally smaller than the average domesticated sheep, and that difference is getting larger and larger. Over the last 20 years, the Soay sheep have started to shrink.
They are becoming gradually lighter at all ages such that today's lambs and adults weigh around 3kg less than those from 1986. Their hind legs have also shortened to a…
laelaps | July 1, 2009
A somewhat tamarin-like restoration of Ganlea megacania. By Mark A. Klingler of the Carnegie Museum of Natural History.
It seems that almost every time a new fossil primate is announced the first question everyone asks is "Is it one of our ancestors?" Nevermind that it is all but impossible to identify direct ancestors and descendants in the vertebrate fossil record (including primates). If the fossil can be construed to be a human ancestor it gets plenty of attention and if it is not the reports are left to wither. For a primate fossil to be seen, it must be promoted, and this often…
edyong | June 30, 2009In a classic episode of the Simpsons, Homer's brain explains to him that "money can be exchanged for goods and services". That's obviously true for humans (even cartoon ones) but monkeys use an altogether different form of payment - grooming. It's as close to a currency as monkeys have and it can be redeemed against a wide range of goods and services including more grooming, a free pass from aggression, permission to handle babies, back-up in fights and even sex.
The purposes of these exchanges go well beyond cleaning. Grooming, it seems, is also an enjoyable activity that releases brain…
laelaps | June 30, 2009
A California sea lion (Zalophus californianus), photographed at the Central Park Zoo.
laelaps | June 29, 2009Against all hope I brought my camera along with me. Special exhibitions do not usually let you take photos, and soon after I arrived at the Discovery Times Square Exhibition with Amanda and her boyfriend J I was forced to hand over all my equipment. No cameras, no cell phones, no food, keep your hands and arms inside the vehicle at all times, &c.
Despite my disappointment, however, it was hard to be sad. I was going to see "Lucy", perhaps the most famous hominin fossil ever discovered, and the B-slab of "Ida", a much older fossil primate that kept me rather busy during the past month. I…
edyong | June 29, 2009If the idea of a cold, motionless sexual partner isn't one of your turn-ons, then you're clearly not an echidna. The males of these spiny Australian animals will happily mate with females even if they're hibernating.
Gemma Morrow and Stewart Nicol from the University of Tasmania have spent the last decade studying the short-beaked echidnas of Tasmania. Over that time, they discovered many instances of males mating with torpid females in deep hibernation, or with females who roused themselves briefly only to re-enter their deep slumber. Over the last two years, the voyeuristic duo use a…
laelaps | June 29, 2009
A young Japanese macaque (Macaca fuscata), photographed at the Central Park Zoo.