Evidence for Evolution- Discovery by Debate Quiz

Answer: The reptiles that live at high densities today are *much* smaller

Some reptiles today live at densities of 20,000- 30,000 per acre- but they are tiny lizards! 30,000 of them weigh much less than 100 pounds. The average size of a therapsid dinosaur from the Karoo was somewhere between the size of a fox and a wolf. Evan at the fox-sized 10 pounds per animal (rather than 80-120 for a wolf) that's 21,000 pounds per acre- a bit more than the weight of an average African elephant! Obviously, a density of one elephant per acre isn't supportable for very long...

Answer: False

There is no relationship between how complicated we perceive an organism to be and its genome size. The organism with the largest genome is an amoeba, Chaos chaos. The average pine tree has a larger genome than the average mammal. The vertebrate with the largest genome is a primitive lungfish. The primate with the largest genome is a tarsier. All of the great apes have larger genomes than humans.

Evolution explains this easily, because much of the DNA in cells does not code for anything (junk DNA) and there are many ways in which DNA can be added to a genome. It is a common misconception that evolution has a "goal" of increased complexity- in reality, evolution has no goals at all.

Answer: Resistance to the AIDS virus in some Europeans

The AIDS resistance resulted from a gene deletion in a protein called CCR5. The AIDS virus normally uses this protein to enter cells. People with one copy of the modified gene are resistant to AIDS; people with two copies seem to be immune to it.

The other adaptations all arose from gene duplication with subsequent modification- protease digestive enzyme in the cod, a clotting factor in the snakes, and multiple incidents of gene duplication in the mosquitoes.

Answer: Deep-sea thermal vents

The iron-sulfur bubbles, which occur near deep-sea vents that exude warm, mineralized water, provide a protective "shell." Within the shell, the iron-sulfur serves as a substrate that can catalyze many reactions. Carbon dioxide and hydrogen sulfide, for example, both plentiful in the waters near such vents, can form acetates, a crucial molecule in organic biology, in such bubbles.

Indeed, even in bacteria today, metabolism depends on acetates that are produced by enzymes that possess the same catalytic composition of iron, sulfur and nickel that is found in the bubbles.

Answer: A testable and falsifiable concept that explains a given phenomenon based on available facts

Creationists rarely dispute gravity, disease causation by germs or the structure of the atom, even though these are very bit as much "theories" as evolution is.

Answer: They have two types of photoreceptors; one found in vertebrates and one in invertebrates

Photoreceptors are cells that sense light. Arthropods and vertebrates have two types of these cells. Vertebrates have ciliary photoreceptors, while arthropods have rhabdomeric photoreceptors. The two types are built by the same gene set and have the same function, but are structured differently.

Ragworms and other polychaete annelid worms are thought to be the last common ancestor of insects and vertebrates. And, when scientists examined ragworms, they found that they have both types of photoreceptors. The rhabdomeric type are found in the ragworm's eye, while the ciliary type are found in a light-sensing organ in the brain.

Ragworms also possess the precursor to what became the hypothalamus in animals with more developed brains.

Answer: Great apes also don't have a working Neu5Gc gene

Cells are covered with chains of complex sugars. At the end of these chains are often various compounds called sialic acids, which help, among other things to regulate water metabolism in cells.

One particular sialic acid, N-glycolylneuraminic acid, is found widely throughout the animal kingdom, including in the great apes. However, humans do not normally produce this particular sialic acid. This isn't because we have lost or never had the gene necessary to do so; instead, this gene has been deactivated by a mutation, and genetic analysis showed that this mutation is approximately 2.9 million years old- after we split from the branch of the primate tree that went on to become chimpanzees and bonobos, and about the same time that a tremendous growth spurt in hominid brain size occurred.

Several scientists have speculated that this mutation helped allow the growth of human brains and also may have allowed human populations to grow due to conferring some disease resistance.

In another fascinating implication, scientists studied the prevalence of variants of this gene in different human populations , which supported a multiple African origin for all human races.

Research has also shown that some tumors can turn the gene back on and produce N-glycolylneuraminic acid.

Answer: All of these

The tests were performed in 1993 by a team led by creationist Steve Austin. The samples of dacite lava that they collected contained xenoliths- pieces of rock that were much older. They submitted their samples for potassium-argon (K-Ar) dating to Geochron Labs, whose website carried a very plain disclaimer that "We cannot analyze samples expected to be younger than 2 M.Y. [million years old]" One of the creationist team members stated "The only information provided to the laboratory was that the samples came from dacite and that "low argon" should be expected.

The laboratory was not told that the specimen came from the lava dome at Mount St. Helens and was only 10 years old." The creationists ran only the K-Ar test; they did not do any of the other tests that would corroborate their findings.

Answer: No

Evolution deals solely with how life changed once it was here. It isn't intended to tell us about how life got here in the first place. Evolutionary theory isn't intended to explain the Big Bang or abiogenesis any more than the theory of gravity is intended to tell us why malarial parasites cause disease.

Answer: The lizards already were very different from those on the mainland

Even though it's difficult to observe species evolving, because it normally happens on a timescale much larger than what humans would notice, it has been observed not just once, but many times.

A recent example of observation of evolution by "Darwinian means" is the incredibly quick evolution of Italian wall lizards on the isle of Pod Mrcaru, as detailed by National Geographic. In 1971, researchers introduced five pairs of lizards to the island. Thirty-seven years later, there are over 5000 lizards on the island, all descended, according to DNA testing, from the original ten lizards. In this amazingly short time period, the originally insectivorous lizards evolved adaptations to a vegetarian diet, stronger jaws, and a different social structure. They are well on their way to becoming a different species entirely.