Monday Science Links

This week's yummy science (better late than never!):

• At Tetrapod Zoology Darren tackles a paper claiming birds can't be dinosaurs: In contrast, say the authors, theropod dinosaurs (non-avian theropods from hereon, thank you very much) lack these features and, worst of all, had a highly mobile femur that cannot have been incorporated into abdominal support - ergo, non-avian theropods cannot have had abdominal air-sacs that functioned like those of modern birds, ergo non-avian theropods were fundamentally different from modern birds. The implication from this - it's not mentioned in the paper but was of course bigged-up in the press interviews - is that birds cannot be dinosaurs! I said a while ago that I wasn't planning to cover this research, predominantly because I don't find it at all interesting nor worthy of review. After all, Ruben and colleagues seem to have made a career of publishing papers in which they assert that 'birds cannot be dinosaurs because of [insert supposed fatal flaw in the 'birds are dinosaurs' model]', and there's no indication that criticism of their conclusions will cause them to stop now. However, a brief discussion held over at Penguinology has changed my mind: we should try and set the record straight. Or, with great power comes great responsbility, or whatever. What makes this research particularly grating is that, like all the other papers by Ruben, Feduccia, Martin and colleagues, the 'birds are not dinosaurs' movement relies on two under-handed tricks that should be exposed.


• At Backreaction Bee asks What do we mean by "fundamental"?: A theory is fundamental if it cannot be derived from another, more complete, theory. More complete means the theory is applicable to a larger range. Note that a fundamental theory can be derivable from another theory if both are equivalent to each other (though one could plausibly argue then one should consider both the same theory). Throughout history, the search and discovery of more fundamental theories in the natural sciences has lead to a tremendous amount of progress. That however is not a guarantee it will continue to be the path to progress. The issue is in the expression “cannot be derived” which could mean three different things...


• At Not Exactly Rocket Science Ed looks at moths that jam bats' sonar: Some insects gained ears; others simply rely on outmanoeuvring their attackers. But one group, the tiger moths, play bats at their own game. When attacked, they unleash ultrasonic clicks of their own to jam the calls of their pursuers, disrupting their ability to accurately gauge distances or even feigning echoes off non-existent objects. This technique has been suggested ever since moths were first discovered to click several decades ago, but Aaron Corcoran from Wake Forest University has found the first conclusive evidence that moths actually do this. They pitted moths of the species Bertholdia trigon) against four big brown bats (Eptesicus fuscus) against each other over the course of three days, in gladiatorial arenas surveyed by high-speed infrared cameras and ultrasonic microphones.


• At Why Evolution is True Jerry looks at the vestigal grasp of infants: In WEIT there is a chapter on vestigial traits, defined as those traits that are evolutionary remnants of features useful in an ancestor, but now either useless or used in a different way. The paradigmatic case is, of course, the appendix, the remnant of a caecal pouch used to digest leaves and vegetation in our ancestors. But behaviors can be vestigial, too. One such behavior is the “grasping reflex” of human infants. When you put your finger into the palm of an infant, it will immediately and securely grasp it. The grasp is so tight that it’s sometimes hard to make the kid let go! It is said — though I have never seen this demonstrated — that up to a couple months of age a baby can hang suspended from a horizontal stick for several minutes.


• And at Cocktail Party Physics, Alex tells us about Dr Walter Cheadle and "case-based reasoning": In 1877 in the well-to-do London suburb of St. John’s Wood, a sixteen-month-old infant is dying. Georgie has cried for weeks, but now he doesn’t have the energy to cry. Too feeble to sit up, he won’t move at all, if he can help it. He can’t bear for anyone to touch his legs, which are covered with bruise-like spots. His face is ash white. His gums are inflamed and spongy. His breath smells like a corpse. The pediatrician, Dr. Sumner, has prescribed chlorate of potash and quinine bark – strong general-purpose medications – and later syrup of iodide of iron and cod-liver oil. For the inflamed gums, he orders alum and glycerin applied locally. But Georgie’s condition only worsens. The swelling of the gums grows still more extensive, until the whole of the mucous membrane of the upper and lower jaw seems to be involved, and the bleeding becomes more profuse. Georgie begins to have spasms in his throat that cut off his breathing. Children die in Victorian England. In the upper-class areas of Liverpool, according to an 1899 report, 136 out of 1000 newborns die before they reach the age of one. Working class districts maintain a rate of 274 infant deaths per 1000, and 509 slum children die for every 1000 born, all within the first year after birth. A very sick child like Georgie, not responding to treatment, unable to eat, having difficulty breathing, is expected to die. But he gets a lucky break.

Enjoy!