Skip to main content

#58: Tardigrades

Litinsects #58: Tardigrades

Anyone recognize these weird-looking little guys? They are actually not insects, as a matter of fact they are not even arthropods but they are cool enough to deserve a post. These are TARDIGRADES, also known as water bears or moss piglets. They are best known for their bizarre abilities to survive some of the most extreme conditions imaginable...

© Science Faction Images

-As always, the name’s etymology describes them a bit. It comes from the Latin “tardus” meaning “slow” and “gradior” for “step/walk”. Their common name comes from the fact that their walk looks a bit like a bear’s

-Tardigrades are a PHYLUM of animals consisting of around 1,300 species. (Side note: the TAXONOMIC LEVEL of a group has nothing to do with how many species it contains. For example phylum Arthropoda, a taxonomically equivalent category consists of around 1 million described species and possibly millions more not yet described!).

-These animals are all microscopic, ranging in size from 0.1-1.2 mm long. They have four stubby pairs of legs, ending in little claws. Unlike arthropods (aka “jointed-leg”) tardigrades do not have jointed legs but they do MOLT like arthropods

Now on to the good stuff... tardigrades have been around about 500 million years, having survived all 5 major extinction events. Their ability to survive crazy extreme conditions makes them some of the most resilient animals that we know of. 

They have been found: in hot springs; 6,000 meters (20,000 ft) above sea level in the Himalayas; 4,000 meters (13,000 ft) below sea level; under layers of solid ice. 

They can withstand: PRESSURES many times greater than those found in the deepest oceans (that’s 1000s of times atmospheric pressure); TEMPERATURES ranging from -272°C (almost absolute zero!!!) to 150°C (that’s -458°F to 300°F) for a few minutes; RADIATION doses 100x higher than what would kill a human; and even the VACUUM OF SPACE.

Now you may be asking (and rightly so) HOW?! Tardigrades have evolved the capability to undergo CRYPTOBIOSIS, a state of extreme metabolic suspension, in which their metabolism drops to 0.01% of normal in response to adverse conditions (such as too little water, too little oxygen, extreme temps, toxins). But once environmental conditions return to normal, they come out of their dormancy and continue right where they left off.

Pretty fascinating little critters!

Labels:

Comments

Post a Comment

Popular posts from this blog

#13: Insect Legs

Litinsects #13: Insect Legs Insect legs can be as diverse as the animals themselves. Some are long and slender like a crane fly’s, some are short and hefty like a mole cricket’s. But what all insects share is the number and layout of those legs. Hexapods have 6 LEGS, a pair each of fore, mid, and hind legs that are made up of the same basic units. Starting closest to the body, they are:  (1) the coxa, which attaches the leg to the thorax  (2) the trochanter (3) the femur, which is oft en the thickest segment  (4) the tibia, often covered in tiny hairs (5) the tarsus, which contains 5 “pseudo-segments”  (6) the pretarsal claws, of which most insects have 2 on each leg The basic units of the leg always occur in this order but may be reduced or highly modified in some species to fit certain tasks such as running, digging, swimming, grasping, or jumping. This photo sums it up perfectly: from < https://wiki.bugwood.org/File:Insect...
Post a Comment
Read more

#22: Caterpillars

Litinsects #22: Caterpillars Since you are freshly familiar with metamorphosis from my last posts, I will today be talking about caterpillars 🐛 and some structures that change drastically in appearance from before to after metamorphosis: legs. Caterpillars are the worm-shaped larval stage of butterflies and moths. They have huge appetites; they mainly feed to grow and gain energy for their transformation into adulthood. In order to do this they need to get around, for which they use le gs because only adult stages have wings.  But insects only 3 pairs of legs, right? So where do all these extra legs come from all down the sides of their bodies?  Caterpillars have 3 pairs of TRUE LEGS, attached to their thorax, which are jointed and have little claws on the end. These legs are still present after metamorphosis, though they will have changed substantially Additionally, they usually have 2 to 5 pairs of PROLEGS, which are protrusions fr...
Post a Comment
Read more

WELCOME: Social Distancing Entomology Course

All week I’ve been seeing videos and posts of the creative stuff people have been doing while social distancing, all the while thinking, what could I contribute to all the people sitting at home on social media all day?? Well this morning it hit me. I will do what I do best! And that is... drop some nerd knowledge on you all 🤓 Welcome to my social distancing ENTOMOLOGY COURSE!  Every day I will post an insect photo, most of which I’ve taken through my microscope, and explain about the insect group or the feature pictured. My hope is that you might learn something new about insects and maybe, just mayyyyybe, be a bit more fascinated and a bit less grossed out by the most diverse and arguably most successful group of animals to ever live... thanks for reading, stay tuned 🦋 🦟 🦗 🐞 🐜 🐛
Post a Comment
Read more