“…as Goethe expressed it, ‘in order to spend on one side, nature is forced to economise on the other side.’”                            {Charles Darwin, 1859} 

Whilst I was in Tasmania recently for an 8 day trek I was lucky enough to see an amazing array of animals (5 Wombats, 2 Echidnas, a Spotted Quoll, 7 Tiger snakes, 2 White-lipped snakes, hundreds of birds and several Wallabies, Pademelons and Kangaroos!) As I took a stroll along the path away from camp one late afternoon, I stopped and watched a ‘mob’ of wallabies grazing. What immediately stuck me was that they were so ridiculously large I wasn’t quite sure how they moved around efficiently at all. Sure enough, when they realised I was there and got startled they (I guess you could call it) “hopped” away. The ground beneath my feet literally shook with each impact of their feet against the earth. They didn’t quite bounce; it was more of a thump-pause-lunge-thump-pause-lunge-thump kind of movement. I had a good giggle and wondered why an animal with this form of locomotion, normally quite elegant and springy in other similar species, weighed what looked like over 80kg. I thought that potentially the extra fat and fur was a trade-off to keep warm in Tasmania’s chilly months. Upon further research at home, I concluded that it resembled the most to a Bennetts Wallaby (Macropus rufogriseus), and was confused to find that they really weren’t that large at all. So, either I’ve discovered a new species of Macropods, or these particular Bennetts had a serious stash of Toblerone out the back.

What the Bennett Wallaby normally looks like - elegant and agile

A more accurate representation of the Bennett Wallabies I saw in Tasmania

A more accurate representation of the Bennett Wallabies I saw in Tasmania

Regardless, it got me thinking about some of the creatures in our world whose evolved adaptations just don’t appear to make sense until you delve in deeper and learn a little more.

Over the next few weeks I will be posting about adaptations that, although initially appear to be detrimental to the species’ survival (or dignity!), have a perfectly logical explanation behind them. Stay tuned to learn about the fight between life and sex, the costs of reproduction, r/K selection theory, sexually selected traits and theories such as the handicap principle and honest advertisement.

I hope to inform and amaze you so that next time you see an animal with a massive nose, ridiculously extravagant plumage or oversized eyeballs, you’ll stop laughing and have a good think about what this species has gone through to get there, and why.

References:

1. Charles Darwin, 1859, On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life, New York: D. Appleton and Company

2. Department of Primary Industries, Parks, Water and Environment (2014), Tasmanian Government, viewed on 9th March 2014

3. http://commons.wikimedia.org/wiki/File:Bennetts_Wallaby_(4995820225).jpg (9th March 2014)

4. http://www.fotosearch.com/JNB013/156181/ (9th March 2014)

5. http://scienceblogs.com/tetrapodzoology/2007/12/18/britain-wildlife-themepark/ (9th March 2014)