21 - 30 of 41 Answers
May 8, 2008:
You stated in an earlier answer that human chromosome 2 is made up of two fused chromosomes from the common human-chimp ancestor. This fused chromosome then spread throughout the human population. Could common design be an alternative explanation? What specifically RULES out common design for the fused chromosome?
December 6, 2007:
What causes changes in DNA? Do accumulative changes in DNA lead to evolution? Could you explain that process to me. How does the DNA know that it needs to adapt? It is my understanding that the germ cells that pass traits to the next generation are isolated from the cells that are affected by the environment. How does that knowledge and or adaptation get passed to the next generation?
November 30, 2007: The field of evo-devo has started showing that big evolutionary changes can happen with only limited genetic changes. Changes in genes that control the expression of other genes can have dramatic effects on an organism. A small change in the expression of one protein can create a much larger and different beak in a bird, for example. So evolution does not require invention of entirely new genes -- just tinkering with expression of the ones already in existence.
Question: Is there any indication that these control genes might be unusually susceptible to mutation? Or maybe there are lots more versions of these control genes, creating more places for selection to act on? If so, this would help explain why evolution sometimes occurs very rapidly.
August 29, 2007:
If evolutionary theories hold true, how did the leap from 24 to 23 chromosome pairs occur from 'apes' to humans? How is it possible for two chromosomes to merge into one, and for the resulting species to survive to breed?
March 30, 2007:
How do we know that evolution isn't a hoax?
December 15, 2006:
Due to slight changes in their genetic makeup, bacteria have been able to successfully develop antibiotic resistance. Would it be possible for humans to develop this kind of resistance as well? Could we make this process work for us and become resistant to, for example, the mutations caused by cigarette smoke or UV light?
October 6, 2006:
All my life I have believed that as humans, we are slowly but surely through the evolutionary process losing our pinky fingers, much in the same way we lost our tails. My 16-yr-old daughter mentioned it to her Anthropolgy/Sociology/Psychology teacher. He asked her to bring in an article supporting the idea; he'd never heard that being postulated before. I've spent HOURS looking on the 'Net -- nothing! Many vague references, hundreds of message board posts that make reference to it, but not one article, not one paper, nothing, that either supports or refutes the idea. I would have thought that our DNA would have mutated to accommodate unnecessary/disused functions of our corporal selves and gotten rid of anything excess. No?
August 10, 2006:
Why when a fish goes into a cave does it eventually lose its eyes? In other words, why did the eyes of cave fish disappear?
June 16, 2006: What kind of genes do duck billed platypuses have?!
April 21, 2006:
In a new species, is the chromosome structure of the genome any different? What might cause the number of chromosomes to change? Would this be a mutation during reproduction? Is this something we see with simpler organisms?