My favourite microscopic creature: Tardigrades

In this weeks blog post, I am going to introduce you to my favourite microscopic creature, the tardigrade. This picture is a tardigrade or water bear.

To me it looks like a microscopic louse. The only difference is the name and the fact that this tiny creature can survive in outer space in the Universe. Yes, you heard me correctly. Outer space in the Universe. It can also survive being heated to a scorching 151 Degrees Centigrade and can withstand a chilling -271 Degrees Centigrade. This temperature is just 2.15 Degrees Centigrade above absolute zero which is the coldest possible temperature possible. It can also survive dehydration as there was reports of leg movement in a 120 year old specimen from dried moss! They can also survive 1,000 times more radiation than other animals and withstand dangerous toxins. Tardigrades and animals like them are called extremophiles.

This creature dates back to the Cretaceous period, which is about 65 million years ago. This was the time when dinosaurs were roaming around the Earth. Now dinosaurs are extinct but tardigrades survived. Tardigrades can be found on lichens and mosses. They are eutelic meaning all the adults have the same number of cells. Some species have 40,000 cells in their bodies while some tardigrades have far fewer. Most tardigrades are one millimetre long when they are fully grown. The biggest adults may reach a length of 1.5 millimetres while the smallest are less than 0.1 millimetres. Newly hatched tardigrades are less then 0.05 millimetres. Most tardigrades eat plants or bacteria but some, like Milnesium tardigradum, are meat-eaters. About 1,150 species of tardigrades have been discovered. Tardigrade genomes are about 75 to 800 megabase pairs of DNA which is not alot according to Broad Institute in the United States of America which is currently sequencing the genome of the tardigrade species.

I think tardigrades are special because they can survive outer space which is not an easy feat. They are amazing and interesting species that look like aliens. They might even survive a mass extinction! This animal is definitely one of my favourite microscopic species.

I would give this animal a 10/10 for their amazing survival capabilities.

Image credit:

Wikimedia Commons (by Darron Birgenheier from Reno, NV, USA [CC-BY-2.0 (http://creativecommons.org/licenses/by/2.0)], via Wikimedia Commons)

http://commons.wikimedia.org/wiki/File%3AWaterbear_(Tardigrade)_from_the_drainage_of_a_hot_spring_in_Lassen_County%2C_California_-_Stacked_Macro_10x.jpg