The theory of evolution has been controversial since its inception largely because it deals with issues of human origins and behavior, our place in the Universe, and life and its meaning. Its implications can be quite disconcerting, but many observations support the fact that organisms on Earth are the product of evolutionary processes and these processes are consistent with what we know about how matter and energy behave. As we characterize the genomes of diverse organisms, we see evidence for the interrelationships, observations that non-scientific (creationist) models would never have predicted and do not explain. That evolutionary mechanisms have generated the diversity of life and that all organisms found on Earth share a common ancestor is as well-established as the atomic structure of matter, the movement of Earth around the Sun, and the solar system around the Milky Way galaxy. The implications of evolutionary processes remain controversial, but not evolution itself.
Scientific knowledge is a body of knowledge of varying degrees of certainty-some most unsure, some nearly sure, but none absolutely certain...Now we scientists are used to this, and we take it for granted that it is perfectly consistent to be unsure, that it is possible to live and not know.
- Richard Feynman.
...it is always advisable to perceive clearly our ignorance.
Questions to answer & to ponder:
•Why do you think vitamin C dependences in Haplorrhini and guinea pigs were independent events?
•What is the mechanism by which traits are lost?
•What typical mammalian traits have whales lost during their evolution?
•Generate a model by which you could classify a trait as primitive or derived?
•How does the loss of a trait or convergent evolution complicate lineage analysis?
•If all organisms are descended from a common ancestor, what can we say about the diversity of pre-biogenic systems that existed before that ancestor?
•What conditions might lead to a complex organism becoming simpler?
•If the environment were constant, would extinction or evolution occur?
•In what ways might organisms direct (or influence) their own evolution?
•What are the benefits and drawbacks of a high degree of specialization for a species?
•How might the types of changes that lead to reproductive isolation be beneficial (overall) even if they were mildly deleterious?
•How do we know that a species is a species if we do not directly observe whether it can interbreed with other organisms?
•Consider Hawaiian honey creepers; which is most likely to become extinct and why?
•What testable predictions emerge from "intelligent design creationism"?
•Under what environmental conditions would a generalist be favored over a specialist?
•What benefit(s) might be linked to the loss of eyesight or other "advanced" traits?