Planet Earth

This evening, I caught most of some episodes of this series the Discovery Channel is airing, Planet Earth, which was advertised here for a while. It wasn’t bad. It had some spectacular photography, did a great job of displaying a wide range of environments, and showed off some of the amazing abilities of animals very well. There were a few things that irritated me, though (I admit it, I criticize everything).

The biggest problem? It’s a show for people with short attention spans. We got brief vignettes of a few minutes—you’d just be getting into the pumas and alpacas in Patagonia, and zip, we’re off to grizzly bears in the Rockies. It was popcorn biology, crunch crunch crunch, you’ve snarfed down a whole bag a few kernels at a time.

That quick glimpse of each biome also meant the focus was entirely on the biggest, most distinctive organisms in the environment, the ol’ charismatic megafauna problem of nature documentaries. For instance, several of the scenes featured whale sharks or dolphins or sailfish chowing down on these great schools of generically named “bait fish”…but hey, wait a minute, aren’t these “bait fish” a rather critical component of the ecosystem? Why not tell us more about them? Treating them as convenient clouds of meat for bigger predators didn’t seem to do them justice.

Still, it was worth watching, and maybe younger kids would have an easier time getting into it. After a few hours exposure, I was feeling a bit whipsawed by the too frequent changes in subject.

Pregnant? Feeling bloated?

Here’s a picture to make you feel relatively fortunate, from the April 2007 issue of Natural History:

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Naked mole rats are odd little mammals in which only the queen of the colony gets to breed. The point of this picture is that even when not near the end of their term of pregnancy, they are recognizably distinct from other rats in the colony — they tend to be much longer. The reason is that the hormones during pregnancy, and probably also the physical stresses on their body, induces the lumbar vertebrae to actually grow longer. Humans, fortunately, do not grow a couple of inches vertically with each child.

Squid washing up all over

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Here’s a story of a strange large squid carcass hauled up from the Atlantic deep—researchers expect it was between 16 and 24 feet long when alive and intact, but the specimen was a bit gelatinous and damaged and nibbled upon. It’s been tentatively identified as Asperoteuthis acanthoderma, which has previously only been found in the Pacific.

Although muscular squid zip around to catch food, squid with gelatinous bodies typically float in deep, dark waters and let prey find them, Young says. Pacific A. acanthoderma have glowing, prey-alluring pads at the end of their tentacles. Sucker-laden tips on the pads’ ends grab curious prey and hold on until the squid moves in to swallow the food.

At least “that’s what we think happens,” Young says. “No one has yet seen one of these animals alive.”

Curing malaria by helping mosquitos

Here’s a clever (I think) observation in the efforts to eradicate malaria: the mosquitos that transmit malaria are also infected with the disease-causing parasite, so maybe if we cure malaria in mosquitos, it will end one intermediate step in the transmission chain. It sounds like a crazy idea, but recent experiments suggest that it might just work. It’s got the advantage of allowing the use of transgenic techniques on the mosquito population, where you don’t have to worry about patient’s rights or whether a few of your experimental subjects will die during the procedure, and you can just let the untreated population wither away and die, and no one can complain. There are a few other ethical concerns, however.

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The lovely stalk-eyed fly

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Sphyrocephala beccarii

Here is a spectacularly pretty and weird animal: stalk-eyed flies of the family Diopsidae. There are about 160 species in this group that exhibit this extreme morphology, with the eyes and the antennae displaced laterally on stalks. They often (but not always) are sexually dimorphic, with males having more exaggerated stalks—the longer stalks also make them clumsy in flight, so this is a pattern with considerable cost, and is thought to be the product of sexual selection. The Sphyrocephala to the right is not even an extreme example. Read on to see some genuinely bizarre flies and a little bit about the development of this structure.

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Coelacanth evolution

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I was reminded of one of the more comical, but persistent misconceptions by creationists in a thread on Internet Infidels, on The Coelacanth. Try doing a google search for “coelacanth creation” and be amazed at the volume of ignorance pumped out on this subject. I’ve also run across a more recent example of the misrepresentation of the coelacanth that I’ll mention later … this poor fish has a long history of abuse by creationists, though, so here’s a brief rundown of wacky creationist interpretations.

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