Thursday, April 15, 2010
I do not intend for this to be an open, theological forum. My challenge is this:
Based on what we know about the different theories of evolution, how would each view point feel about the above question? What aspects of human anatomy, fossil record, and sociology would affect these views. Please compare Creationism, Intelligent Design, and forms of Darwinian evolution.
Then, BRIEFLY share your own views on man's place in the universe.
Wednesday, April 14, 2010
We use language in our everyday lives to ask for something, exchange opinions, and learn about different ideas. Language is obviously very important, but why did it evolve in the first place? Better yet, why do we have so many languages instead of simply one? Wouldn’t it be easier to communicate with all different people without this language barrier? In addition to broaden the subject, in the Campbell Biology book we read about how different organisms communicate. One of creatures was the honeybee, which dances in order to exchange information with its hive about the location of food. The honeybees don’t simply point a direction, but they also give the distance of the food with their extravagant “waggle dance”. What are other ways organisms communicate that don’t use speech like we do? Give an example and, if possible, the reason it may have evolved.
Tuesday, April 13, 2010
This is a list of 16 states that directly or indirectly encourage ID to be taught in schools, Not the geography of the states and comment on why you think the distribution is so.
From here, take several ideas from the creationist side and refute them using either examples from the book but also using the idea that evolution is a science.
On page 141, Coyne explains how complex organs like the eye would have been created over the course of time by giving a series of examples with intermediary steps of said organ as can be found on animals today. But how could natural selection ever dictate that a blood vessel as crucial to the proper functioning of the body like the carotid artery would be placed so close to the surface of the skin, exposed and in great risk of being accidentally cut? This is just one example, another being the spinal column. It is illogical to think that such an important part of the nervous system would be surrounded by vertebrae and gelatinous discs that with one false move can sever the spinal cord and majorly disable a person. What other illogical body parts exist on humans that are either too vulnerable or exposed for natural selection to warrant their placements? On other animals? And how can evolution explain these simple vulnerabilities?
Monday, April 12, 2010
Also, humans have the incredible ability of imagination. I can tell you to imagine a spherical chicken, and you can do it, but a dog cannot. It can be taught what a sphere is or a chicken, but it cannot combine the 2 concepts to imagine what a spherical chicken is.
What are some possible ideas that counteract this argument? Consider, can physical reactions between neurons really give rise to non-physical entities?
Coyne claims that the fossil record is important for three main reasons (pg 53). Can you list other reasons that the fossil record is crucial to arguing for evolution (you may elaborate on Coyne’s three points)? It may help to name a few examples of species that support the assertion of the significance of the fossil record in the entire scope of evolution (gradual change within lineages, etc.)?
cognitive structure, like physiological structure, has been designed by natural selection to serve survival and reproduction". Based on what you know about natural selection, how is it that the concept of evolution may be reasonably applied to psychology? What situations may have selected for the development of emotions? Cognitive thinking, problem solving, social cooperation, altruism? How has this impacted our social structure, values, morals, beliefs etc. ? How can evolutionary psychology be applied to "survival of the fittest" in modern day society?
Sunday, April 11, 2010
And if yes, use your knowledge of evolutionary theory to explain why it would seem logical to believe that there are other intelligent forms of life.
What would you say to convince a hesitant person, who is trying to decide whether to believe in evolution or not? This person expresses the doubt stated above and needs an AP bio student to convince him/her otherwise. (Use 224-233)
We have learned that it takes more than an organ's shape to make it function properly. There is a whole network of proteins, hormones, tropic hormones, pH and salinity balances at work. My question is this:
How does feedback allow for complex organs and systems to function in our own bodies? When is there a selective advantage for positive feedback, and when is there an advantage for negative feedback? Why does this difference exist?
Saturday, April 10, 2010
Coyne cites “bad design” as an argument against creationism. Vestigial organs are one example of bad design like our appendix. Coyne also gives examples of odd design that shouldn’t be created by an intelligent designer. One example of this is the flatfish; as opposed to other fish, the flatfish swims on its side and has deformed features. (82)Find an example(s) of bad design in organisms, like in the flatfish, and describe the functions of traits/structures and give a possible evolutionary basis for that trait. Explain why bad design is evidence of evolution and also write why creationists are so keen to avoid the topic of bad design.
Friday, April 9, 2010
According to Jerry Coyne, ecosystems are incredibly vulnerable. As he addresses, “island ecosystems… are fragile things, easily ravaged by foreign invaders who can destroy habitats and species,” (110). The worst, as he adds, are humans themselves. We’ve seen the destruction of the rainforests for trees and land, as well as land in our own towns destroyed to make homes and buildings. As Coyne continues, “each species represents millions of years of evolution and, once gone, can never be brought back” (110). What lengths are humans going to to protect ecosystems and preserve their habitants? Also how are we restoring habitats that might have been damaged by humans? Coyne’s also brings up the point that we bring over organisms into different habitats that the environment isn’t adapted too. Give an example of an animal that has invaded a foreign habitat and the results of its invasion. If possible, explain how humans are trying to fix the problem and restore balance to that environment.
Give another example of an animal or plant that humans have transformed for their own needs or desires. Do you think that through breeding humans are meddling with natural selection and disrupting the evolutionary process or is this just another factor influencing evolution. Explain and provide strong support for your opinion.
Coyne brings up the point that certain groups of organisms are considered to be separate species even though they look exactly alike. For example, the group of fruit flies, Drosophila, is recognized as nine separate species due to differences in where they live and who they bite. Conversely, there are groups like humans that look very different, yet still have the ability to successfully mate together and are considered the same species. This brings up the question on whether or not "designation of species is an arbitrary exercise" or not (171). Therefore, what advantages are there to organizing the species into phylogenetic trees even through there are obvious inconsistencies and debates within the system?
Thursday, April 8, 2010
Coyne classifies two types of islands, continental islands and oceanic islands (page 100) Evolution uses these two types of islands to point out that the oceanic islands that are missing similar types of species so if a creator had made all the animals everywhere than this wouldn't be the case. Coyne then goes on to explain that this is an example of the "blend of chance and lawfulness" (page 109) of evolution when distributing life on earth. First, define the two types of islands. Then find examples of species that are found on main lands and continental islands but not on oceanic islands. Explain how oceanic islands can be considered to always have been separated hence why evolution of certain species did not occur there when the well established principle of pangea is accepted as truth. If all of the land was once together than wouldn't evolution occur similarly on all of the land that broke off? Not just some of it? Doesn't calling evolution a blend of chance and lawfulness give support to Creationism? If evolution is one large part chance that we do not explain in a scientific way then isn't there a gap open for divine intervention? How is it chance that the birds migrated to the Galapagos islands, they must have had a scientific reason for leaving where they came from in the first place and another reason to stay on the island therefore how is that chance at all? Use examples in your explanation.
In the chapter The Origin of Species, Coyne describes how the majority of species that form the diversity of the biosphere we live in. The predominant pro-evolution theory is that different species were caused by a single population being separated geographically and evolving in a different manner from its distanced kin until a point where if the two populations were reintroduced, they would be unable to reproduce with each other and therefore recombine their genes. However, can we really expect that of the millions (and perhaps billions depending on the classification system) of species in the world that they all were separated by a landmass forming across the sea or a mountain chain rising amidst a forest? Granted that the earth has been around for a long time and that the planet has changed a lot since life first inhabited it but what other possible ways could a population evolve separately from another population of the same species to the point where it can no longer share genes and becomes a different species? Dr. Coyne also gives the example of flowers adapting to different pollinators and therefore not being able to recombine their genes so obviously this one is exempt.
Wednesday, April 7, 2010
How would killing of the parasite's host be beneficial to the parasite, if it will die as well? Would it not seem logical that genes would be selected that stop the parasite from growing too large or too harmful, to maximize its own life span, and thus its reproductive success?
1: Campbell, P. 1202-1203
In Coyne’s harrowing tale of the Asian giant hornet he describes a specific prey adaptation of the Japanese bee in order to combat the hornet upon an invasion of their hive (112). He also gives one other example of a predator/parasite-prey evolutionary relationship with the example of a roundworm infecting an ant in Central America but this point for evolution is rather scarcely covered with examples. What other examples are there of complex and specific predator (or parasite) to prey relationships where the predator is well adapted to hunt its prey and the prey has evolved specific defenses as a reaction to these recurrent attacks? Also is it not also true that, in time, predators would begin to adapt to the strategies used by their prey to fight them off? Provide another example for this case where the predator is adapting alongside its prey.
On pages 175-176, Coyne describes what he calls divergent selection, based on geographic barriers in flowering plants, hummingbirds, and bees. He suggests that in one isolated region containing more hummingbirds than bees, flowers may evolve to become better suited to pollination by hummingbirds than bees- and the other way around in a region characterized by more bees. Then he speculates, that over time, should these two types of flowers that have evolved distinctly from one another suddenly be placed in the same location, the geographic barrier having disappeared, and the area containing equal amounts of bees and hummingbirds, then these flowers would each have their own type of pollinator and would not cross pollinate as a result, for they are now two different species. How difficult is it to maintain the ability to mix genes with closely related species (defining species by the definition given on page 172) or at least with those species derived from a common ancestor? Why would different species adapt their reproductive organs to become better suited for their own species rather than a wider range of potential mates? Wouldn't it be to the advantage of the flower placed back in the location described above to be able to be pollinated by both bees and hummingbirds? To what extent would it not? Why don't we see greater potential to mix genes and reproduce across species if sex has evolved as a means for genetic diversity?
On pages 39-47, Coyne talks about how birds evolved from reptiles. He explains reptiles began to have asymmetrical feathers to aid in flight and opposable big toes for perching. Why would these changes be beneficial for the reptiles' survival? From this evolutionary break, birds have evolved into a variety of different species due to the demands of their respective environments. According to www.birdlist.org, there are at lease 10,031 species of birds on the planet! Choose a specie of bird and explain in detail how it has evolved from its distant ancestor to fit its environment. Are there any ways in which this specie of bird does not fit its environment? Explain.
Tuesday, April 6, 2010
The sensory-bias model, as Coyne outlines on pages 166-167, suggests that sexual dimorphisms evolved as a result of biases in the female nervous system – whether it be like the theoretical example that he shared with the mutant male's red coloration on his breast stimulating the female's visual preference for red color, or simply, a stimulation of the nervous system as a result of more extravagant displays. Consider why these preferences are so nonspecific; why might it be 'better' to recognize the red coloration rather than a certain chemical secretion? And to what extent do these animals have to recognize and 'appreciate' different behaviors or physical adaptations (such as shiny fur or long mating calls)? Why might females have adaptations to be able to process these different adaptations on males? Why spend more energy, for instance, developing eye spots to visually choose males if that's their only purpose? Is it worth it?
Coyne states, in passing, while offering examples about male competition and sexual selection, that “Females, who don't have to fight, are presumably close to their optimal weight for reproduction” (150). It is shown that “direct competition between males” and “female choosiness” (148) are apparent among organisms, and a key to sexual selection. As a result, it is arguable that males would tend to change more than females in order to increase their fitness and opportunity to produce offspring. Coyne already addresses the issue of the tradeoffs between adaptations benefitting survival and those aiding in reproduction in males; though there are many seemingly energy intensive/wasteful traits that males have to “win over the females”, they tend not to become so elaborate that these adaptations would result in the death of the organism before they even have a chance to pass of their genes to their offspring. However, in females, this becomes more of a question; since they tend not to have to fight for males, and do the choosing of their potential male mates, how is it that the females are able to adapt to become more suitable for reproduction? It would seem as if the males would tend to undergo selection “faster” than females do. Also, how far does this go? A deer's antlers can only get so large; with males having the largest, most robust antlers winning more jousting contests and impregnating more females. With this type of selection, wouldn't it be reasonable to presume that the deer's antlers would approach a certain maximum size (consider the tradeoff with survival and reproduction – at some point, the antlers would hinder their ability to survive). Speculate as to what happens in this situation.
When I hear or read the term evolution I immediately connect it with a song by a rather unheard of Punk-Rock band called NOFX, the song is titled “The Idiots Are Taking Over” (Lyrics: http://www.lyricsondemand.com/n/nofxlyrics/idiotsaretakingoverlyrics.html and please excuse the expletives) but the song itself deals with the political ramifications of a possible reversal of evolution in human populations, the band argues that since the Industrial Revolution the fittest of our species have no longer been the only survivors and not only that but the unfit are producing more offspring and further propagating their “worse” genes. Their argument brings up a good question: Has humanity come to a point where natural selection no longer applies, where random mutations that cause lower fitness in a human actually get spread throughout the gene pool? Support your answer, and if so: What will the potential effects be on humanity as a species in the future?
Monday, April 5, 2010
As Coyne describes on pages 121-122, when invading lions displace resident males of a pride, they slaughter all the unweaned cubs so that the females will come back into estrus (since they are not nursing the cubs anymore, they will be ready to conceive again). By the theory of evolution, as Coyne has outlined throughout the book, this act benefits the fitness of the individual, by increasing the invading lions' reproductive output, though at the expense of the species as a whole, thus increasing the likelihood of extinction. For this 'gene causing infanticide' to have been acted upon by natural selection, it must first have resulted from a random, genetic mutation. Speculate as to why this gene causing infanticide may have been selected to recur throughout the population of lions, taking into consideration any issues of resources and energy on the part of the females in nursing their cubs, as well as the advantages for the lions' mode of development; in other words, how much do lions nurse their young, and what limitations or burden does this place on the female lions in their inability to conceive while nursing their unweaned cubs? Why would it not be feasible for female lions to have had natural selection act upon them to shut off the gene that prevents them from going into heat while nursing? (Perhaps it is not in the interest of the invading males individual fitness to allow the old cubs to live, but it might increase the fitness of the females to do so.)