Skip to main content

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.

Comments

Post a Comment

Comment...

Popular posts from this blog

4 Reasons Google's Calico Won't "Solve Death"

The on-line world has been taken ablaze by Calico's bid to end ageing, and thus death itself, but is this what they will actually focus on, and will they achieve it? The fact is ageing will be reversed, and death by "natural causes" will go with it. The questions are "When?" and "By whom?". Until recently, not a lot was known about the approach Calico would take in this venture dubbed "moonshot thinking" - a term touted by Google as the source of all considerable human progress throughout history. This we don't doubt, but is this what Calico is all about? CNN's Dan Primack has revealed details about Calico's plan , which hint at a less-than-moonshot thinking approach, and cast a serious question mark on its ability to deliver the punchy TIME headline. Here is why: 1. The man with the idea, Bill Maris, arrived at the conclusion that the root of all death-causing disease is simply ageing itself. Not only is this widely ...
11 comments
Read more

Principles of Evolution - Sexual Selection

If it weren't for sexual selection, evolution itself would be a passive process. Natural selection isn't sufficient in the evolution of life, because it does not deal with predictions of future selection pressures. For example, if a massive natural disaster were to wipe out every single collared pigeon on Earth, then there would be no process in place to bring the collared pigeon back to life. Since the development of the pigeon from its ancestor must have taken a very long period of time, it is a really inefficient idea to just let the pigeon's fate hang by chance. Admittedly, if all members of that species were to be wiped out, the chances of it being reintroduced would be very close to zero. So, how does sexual selection work to avoid such fates of death of a species? Firstly, let's establish that sexual selection is not the process of reproduction, or self-propagation, but the process by which certain properties are chosen over others to deal with potential future...
3 comments
Read more

Alien Life

Alien life, what an exciting topic! Let's investigate some principles of life which might help illuminate what life forms there are on other planets. One of these principles states that "not all life that can exist does, but all life that cannot exist does not". What this means is that, just because we have discovered certain chemical and physical environments that suggest a life form (for example an earth worm), doesn't mean that an earth worm exists there, or that it will ever exist. However, if the environmental properties are analysed accurately, then it is possible to make an assumption that it is likely for a certain life form to have existed there, or for it to be likely to sometime develop there. The reason why "all life that cannot exist does not" is fairly obvious, either because life will not develop in unfavourable conditions, or because life in unfavourable conditions dies. Another result of that principle is that evolution never reaches a dea...
2 comments
Read more