Organisms
pharyngula | January 2, 2007There's some pulse-pounding high speed insect racing action going on in this animation, and one excellent dipteran crash, but otherwise, not much resolution to the story, and the nice spider gets shafted.
And I was rooting for the spider.
pharyngula | December 30, 2006I don't think I showed this video in the flurry of Architeuthis posts a while back, but if so, it's worth seeing again.
It is rather sad how limp and exhausted the poor animal looks as they drag it in.
pharyngula | December 29, 2006Euprymna tasmanica, camouflaged with mucus and sand
Figure from Cephalopods: A World Guide (amzn/b&n/abe/pwll), by Mark Norman.
pharyngula | December 27, 2006Allow me to introduce you to a whole gigantic superclade with which many of you may not be familiar, and some other groups in the grand hierarchy of animal evolution that I've mentioned quite a few times before, but would like to clear the fog with some simple definitions. Consider this a brief primer in some major animal groupings. Here's a greatly simplified cladogram; I've left off quite a few groups to make the story simple.
I have a frequently admitted bias: I'm most interested in the evolution and development of the Metazoa, or the multicellular animals. I don't follow the literature…
pharyngula | December 23, 2006Almost ten years ago, there was a spectacular fossil discovery in China: microfossils, tiny organisms preserved by phosphatization, that revealed amazing levels of fine detail. These specimens were identified as early animal embryos on the basis of a number of properties.
The cells were dimpled and shaped by adjoining cells, suggesting a flexible membrane—not a cell wall. This rules out algae, fungi, and plants.
The number of cells within each specimen was usually a power of 2. This is something we typically see in cleaving embryos, the sequence from 1 to 2 to 4 to 8 to 16 cells.
They were…
pharyngula | December 22, 2006Since it is Cephalopodmas, I think it's only fitting to throw in another Friday Cephalopod, the psychedelic Wonderpus.
Wonderpus
Figure from Cephalopods: A World Guide (amzn/b&n/abe/pwll), by Mark Norman.
pharyngula | December 22, 2006Look! It's a dumbo octopus! There are some very good shots of this weird creature swimming near the middle.
pharyngula | December 22, 2006Everyone knows you're supposed to be reading Deep Sea News today for all things cephalopodial, right?
pharyngula | December 22, 2006Octopus berrima
Figure from Cephalopods: A World Guide (amzn/b&n/abe/pwll), by Mark Norman.
pharyngula | December 22, 2006Well, if we can't find the new Architeuthis video, we can at least enjoy a little Cephalopodmas carol, Squid and Whale.
If you'd like something more traditional, here are the lyrics for the Twelve Days of Cephalopodmas. You already know the music.
Lastly, should you really want to get into the festive spirit of the holiday, here are some photos of a whale necropsy. Warning: there is blood, there are guts. How much? Well, they used a large backhoe as a retractor.
pharyngula | December 22, 2006
We have a sign: there are reports
of a new video from Tsunemi Kubodera of an Architeuthis—unfortunately, I haven't been able to find a copy of the video online anywhere yet. If anyone finds it, let me know!
There's a small and rather grainy copy of the video on the BBC website!
The copy at CNN is of much higher quality.
pharyngula | December 21, 2006Oh, man, I feel for the kids nowadays. When I was an itty-bitty dinosaur-happy tyke, it seemed like there was a manageable amount of Latin nomenclature you had to memorize to keep up with the dinosaur clan. Now it's like there's a new one added every week, and you've got to be a freakin' genius to be able to follow them all. Kids do still go wacky over dinosaurs, right? We haven't gone so far down the tubes that the little nerds are neglecting their paleontology, have we?
Anyway, there's a new one out of Spain, Turiasaurus riodevensis, an old school sauropod, and it's a big one. Pictures…
pharyngula | December 21, 2006
I've just read the article on the parthenogenetic Komodo dragons in Nature, and it's very cool. They've analyzed the genetics of the eggs that have failed to develop (the remainder are expected to hatch in January) and determined that they were definitely produced without the aid of a male.
We analysed the parentage of the eggs and offspring by genetic fingerprinting. In the clutches of both females, we found that all offspring produced in the absence of males were parthenogens: the overall combined clutch genotype reconstructed that of their mother exactly. Although all offspring were…
pharyngula | December 21, 2006
What are the key ingredients for making a multicellular animal, or metazoan? A couple of the fundamental elements are:
A mechanism to allow informative interactions between cells. You don't want all the cells to be the same, you want them to communicate with one another and set up different fates. This is a process called cell signaling and the underlying process of turning a signal into a different pattern of gene or metabolic activity is called signal transduction.
Patterns of differing cell adhesion. But of course! The cells of your multicellular animal better stick together, or the…
pharyngula | December 21, 2006Let me tell you a story.
Depending on the point of view, it's either a bit of daily routine, or a tragedy.
(via My Confined Space)
pharyngula | December 15, 2006
(From the Olympus Bioscapes International Digital Imaging Competition)
pharyngula | December 13, 2006This sad jumble of bones is all that remains of Volaticotherium antiquus, a small rat-sized mammal that was recently dug up in China. There are two particularly outstanding things about this creature.
One is that browner layer in the rock: that isn't an artifact, it's a bit of soft tissue that was preserved, called a patagium. A patagium is a thin membrane stretched between the limbs, and is used for…flying! This animal probably lived much like a modern flying squirrel (although it is definitely not a squirrel), gliding from tree to tree.
The second surprise is the age. This is a Mesozoic…