Watchful eyes, thoughtful mind

Earth and us ….. past, present and future ….. connected?

Of midgets and giants July 16, 2009

Filed under: animals,biology,evolution,oceanography — Radiance @ 12:00 AM
I didn’t know that in island environments small mammals (e.g. rodents) tend to evolve to be larger (Island gigantism), and large mammals (e.g. elephants) tend to evolve to be smaller (Island dwarfism). This is not considered to be evolutionary trend by some due to the fact that different parameters apply in an isolated island environment. Wikipedia telle me that J. Bristol Foster published his work in 1964, now known as ‘Island rule‘, in which he suggested the simple explanation that smaller creatures get larger in the absence of the predators they had attracted on the mainland and larger creatures become smaller with the absence of food sources. An article in Science Daily suggests, however, that the original size of the species was said to be the key determining factor in these changes. And that the new research by a group in Imperial College London have shown that “bigger becoming smaller and vice versa” is not always the case and varies depending on each islan’s environment.

Interestingly, recent research in marine biology led by MBARI postdoctoral fellow Craig McClain suggests that a similar trend affects animals as they adapt to life in the deep sea. However, once again the trends are not uniform from species to species and the causes are not very clear either. So in general, it looks like we’ve still got quite a bit to learn about our fellow Earthlings in isolated environments.


2 Responses to “Of midgets and giants”

  1. Teresa Silverthorn Says:

    Wow, I didn't know that, either. But, it makes perfect sense.

    Does that explain why I'm short? lol

    Thanks for the info, Radiance…fascinating.

  2. Radiance Says:

    Thanks for the comment, Teresa. I don't think it would explain you being short 🙂 but there are discoveries of hobbits in Indonesia etc. and there's a theory that this could be true for humans as well. Anyway, good to know you enjoyed reading the post :).

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s