Mary Schueler, Ph.D.
This expert's focus:
Comparing the DNA sequence of essential chromosomal regions from multiple primates to define functional changes that have occurred during evolution.
: Generally, human DNA is most similar to more closely related species like the great apes - chimp, gorilla, and orangutan. These are more closely related to us in evolutionary time. Species that have been separated from us for longer periods of time share less similarity. As you compare with species farther away from us on the evolutionary tree, we observe that DNA sequences that code for proteins are conserved while other sequence is not. This is thought to be due to the necessary function of the proteins in the life of the cell. If the sequence changes, the cell can't survive. We are less than 90% similar to most other species. Even within the primate lineage, as compared to old world monkeys, protein coding sequences can vary by as much as 15% (be 85% similar). As you move further away to mice and flies and yeast, the percentage similarity falls off quite a bit.
“More like less than 80% DNA homology between humans and rats, not 97%. What is your motivation for making up numbers without knowledge of the subject. What are you trying to indicate by such an obfuscation?”
Sorry I was incorrect, but I wasn’t just making up numbers. I was attempting to recall the number that I read at the Fernbank Science Exhibit on DNA. If their information is incorrect, I apologize. Or if my memory failed me. However I am not trying to “indicate” anything. And your snobbish assumption of me making up the information I posted is disturbing.