News from the Cretaceous
Here are some recent stories about extinct reptiles and bird-like creatures from the age of dinosaurs.
- T. Rex Smelled Good: A story in Science1 listed evidence that Tyrannosaurus rex had a large olfactory bulb, giving it a good sense of smell. Analysis of the visual and auditory parts of the skull suggest that it also excelled at sight and hearing: “new studies show that the tyrant lizard’s sensory apparatus was indeed fit for a king,” wrote Erik Stokstad. Phillip Currie (U of Alberta) was impressed: “The more we look at T. rex, the more sophisticated it is.” There was no mention of evolution in the article.
- It’s a Bird – It’s a Plane: After researchers suggested last month that the odd Chinese feathered fossil Microraptor gui flew like a biplane (10/24/2005), a fight broke out in Nature.2 Kevin Padian and Ken Dial gave seven reasons why the evidence does not support the idea, and complained that the researchers should not have claimed it supported the arboreal (tree-down) theory for the origin of flight. “It is recognized that the arboreal versus cursorial dichotomy of models for the origin of bird flight is not capable of resolution,” they said, “and should have been abandoned long ago. Rather, the origin of the flight stroke is the central problem in the origin of flight, and so far nothing has been brought to light to indicate that Microraptor has any bearing on this question.” The Chinese are sticking to their story and deny the debate is dead. They believe that Microraptor argues against the cursorial (ground-up) theory. They also said that Microraptor had the same flight capabilities as Archaeopteryx.
- Missing Mosasaur Link? A press release from Southern Methodist University told about a fossil find by an amateur of a mosasaur-like animal with short stubby legs. LiveScience reprinted the claim that it represents a missing link between limbs and fins.
- The Early Turtle Gets the Limb: BBC News reported a fossil leg of an “early turtle” claimed to be 120 million years old. They think the new species was partly adapted to land and partly to sea.
- Prairie Dinosaurs: There wasn’t supposed to be grass when the dinosaurs roamed, but now it’s been found in their droppings, reported LiveScience. Titanosaur coprolites showed phytoliths that indicate the presence of grasses in their diet. “This discovery could also cause a major shake-up in dinosaur dioramas around the world,” the article says. Perhaps vistas of sauropods grazing alongside the buffalo?
1Erik Stokstad, “Tyrannosaurus rex Gets Sensitive,” Science, Vol 310, Issue 5750, 966-967 , 11 November 2005, [DOI: 10.1126/science.310.5750.966].
2Brief Communications Arising, “Origin of flight: Could ‘four-winged’ dinosaurs fly?”, Nature 438, E3-E4 (17 November 2005) | doi:10.1038/nature04355.
In most of these stories, the researchers delved beyond the data into imagination. Creatures adapted to their many and varied environments do not necessarily imply common ancestry. If we must assume the mosasaur-like animal was evolving into a sea creature, for instance, does this mean beaver paws are evolving into fins? Many animal groups have representatives that live on either sea or land, or both. There are sea snakes, sea turtles, sea lions, sea otters, sea iguanas, sea spiders, sea birds and Sea Peoples (that’s what historians call the ancestors of the Philistines). Biodiversity does not presuppose Darwinism; it is what Darwinism needs to explain. None of these stories explain how the highly-adapted, complex structures of the creatures arose in the first place.
The fun part was the spat between the Chinese and Kevin Padian and Ken Dial (Mr. Aerofoil-Partridge; see 12/22/2003) over whether the lizard flapped its arms on the way up the hill, or on the way down from the tree limb. Come back when you get it all worked out, guys. Solve the power stroke, too.