Imperfect (Bad) Design

Creationists claim that a “supernatural” intelligent designer may have created imperfect features for unfathomable reasons; how would you respond to this assertion?

Coyne mentions some “bad designs” relating to evolution – that connect to the useless wings of kiwis, to the vestigial pelvis pelvis of whales and the pelvis of the human body. Can you explain in depth other examples of such imperfect design (page 81)? How do they substantiate why evolution is true (or even, why evolution may not be exactly true? – this link may help: http://www.evolutionnews.org/2009/05/the_myth_of_vestigial_organs_a.html) ?
Finally, how do such traits demonstrate why “the idea of perfect design is an illusion”?

Reproductive Success

In mammals, males often have greater variance in reproductive success than females, as a result of sexual selection. How will this alter the effective population size of genes on the autosomes, the X chromosome, the Y chromosome, and the mitochondrial genome? What other factors may influence the genetic diversity on these different parts of the genome?

Love?

After reading through the book, it appears that animals mate purely by selecting mates that will create "direct or indirect benefits" (Coyne 162). This makes animals sound emotionless and heartless, however, there have been evidence that question an animal's capacity for emotion. (see Source) Can animals truely experience emotion? State evidence, theories, or studies. If animals do indeed experience emotions like those we humans experience, what about love? Can animals "love" one another? Examine how socially monogamous animals pick their mates, and how truly monogamous they are, since Coyne does mention the promiscuity of even socially monogamous animals.

Sources:

Why Evolution is True

Do animals have emotions? http://www.newscientist.com/article/mg19426051.300-do-animals-have-emotions.html?full=true

The Human Missing Link

Scientists hoping to provide more evidence of evolution often attempt to locate fossils that are the most recent common ancestors of two species that are extant today. This common ancestor is called the missing link. On page 194, Jerry Coyne states that even Darwin “remained unconvinced that natural selection could explain the higher mental faculties of humans.” Thus, we needed to find fossils in human ancestry that could show our own evolution. What were these fossils, and how did it help us show that our mental faculties did indeed develop by natural selection? Also, the exact missing link that would provide us our most recent common ancestor with chimpanzees and bonobos has never been found. What would such a link look like, and what kind of effect might it have on the scientific community and the public at large if it was found?

No "downhill slope" in selection

On pages 119-120, Coyne talks about how natural selection must provide a direct benefit to its possessor. He claims that there is no "going downhill in the evolution of adaptation." Sickle-Cell Anemia is a genetic, blood disorder that causes "red blood cells to assume an abnormal, rigid, sickle shape." The change in the structure of hemoglobin causes many complications in life, among which is a much shorter life expectancy (even for people in the USA w/ top of the line medical treatment, ave. life expectancy for one who has sickle-cell anemia is around 42-48 years depending on gender) (1). The defect which causes sickle-cell anemia occurs more often in those of tropical, sub-tropical, decent. As many as one-third of people indigenous to the Sub-Saharan region carry the gene for sickle-cell anemia. This mutation in the hemoglobin gene causes the carrier to become resistant to malaria.

If natural selection is only supposed to provide benefit to the organism, why would this degeneration of the red blood cell be an evolutionary advantage? How could this defect have been proliferated if the offspring would have a decreased chance of survival? After all, the individual may be more fit, if the offspring does not survive to reproductive age, it is no different than not having offspring, which means that genes are not passed down.

1: http://en.wikipedia.org/wiki/Sickle-cell_anemia

Cooperative and Antagonistic Behaviors in Lions

Coyne states on page 119 that "Selection has to explain behaviors, both cooperative and antagonistic". However, these behaviors don't always necessarily appear separately in nature. The lion is a prime example of this. Although living in a highly organized and cooperative social group based on mutual aid in hunting and defense, individualistic tendencies also sometimes take hold in the form of mate competition. In fact, male lions have sometimes been known to kill a lioness' cubs by another mate before reproducing with the lioness. How can such behavior, that may seem very counterproductive in a highly organized social group, exist in the same species that hunts in a cooperative unit? What other examples of organisms can you think of that have a similar structure? Feel free to mention behaviors we have discussed in the ecology unit (ie kin selection, altruism etc).

The Missing Link

Ever heard of a mer-cow? On page 48, Coyne pokes fun at such a transition that could occur between terrestrial and aquatic mammals.

What does Coyne give as an example of a creature that is dependent on both land and water without evolving? Can you research any other creatures that may create a similar scenario? Furthermore, in respect to this transition of animals moving from land to water, like the whale, why did such a phenomenon occur (disadvantage and advantages)? Comment on the transitions found between old and new evolutionary changes (page 53; ex. Wings of bird from the legs of dinosaurs, etc.)