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hmmm, and DNA

You know what, I've been getting a ridiculous amount of visitors lately, and I don't know why, cos I haven't been writing much lately. Uni is good, doing DNA stuff at the moment, and I was reading about something quite interesting.

Until relatively recently, species and their ancestry was determined mostly by things such as physical appearance and function, i.e. two species look similar, so they must be closely related. Funnily enough, after DNA technology took off and it was possible to determine how closely related species are to one another, a lot of these associations and assumptions that were wrong could be rectified. That similarly looking species may not actually have a recent common ancestor, and different looking members of the same species share most of their genetic make-up. Look for yourself.
Flying squirrels on different continents developed their flying wings in parallel with each other, and don't in fact have a relatively recent common ancestor. 


These dogs however look so different yet they are both part of the same species and likely have a very recent common ancestor i.e. great great great great grandparent.

DNA is key to determining evolution in this sense, much more so than simple physical similarity that we as humans are likely to be biased in.

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