![]() ![]() In fact, most Triops in the Northern Hemisphere are females-they outnumber males by at least 100 to 1 but, no problem, they can produce eggs that hatch without fertilization (if you look for Triops in the tropics, you will find more males than females).Īs adults they are quite odd, to human sensibilities anyway. Note: Nothing was said to the effect that they mate and lay eggs. They lay eggs, and the cycle begins anew, as it has for 220 million years. It’ll have maybe three months to live, feeding on tiny aquatic creatures such as worms, frog eggs, other Triops-survivors can’t be choosey. Once out of the egg, the young Triops can mature in just a few weeks, growing to about 1.5 inches long. Even so, if they eventually get to water, they will hatch. They’ll lie in the dirt waiting for the next rainstorm to revitalize them, or they may be blown around by the wind. If the water dries up, the eggs may remain fertile for 25 years (sometimes the eggs are sold in packets and can be revived and grown in an aquarium). And they can withstand horrendous amounts of drying. They lay their eggs in water, and the eggs can survive freezing and, even more amazing, they can tolerate temperatures up to 176 degrees F, only 46 degrees short of boiling water. They are not particular about the water-fresh or brackish will do.Īnd they are tough. Shield shrimp live in ephemeral ponds (temporary ones that dry up), ditches, even puddles. What It Takes to Last as a Species for 220 Million Yearsįirst, you can’t ask much of the world. Then come back, and we’ll discuss what it takes to last as a species for 220 million years. A photo is worth a thousand words, and you probably don’t want to read another thousand words describing this creature, so please refer to the photo. Precisely! The creature is rounded at one end, resembling a horseshoe crab in body, except that it has a longish, segment backend. It’s also called a tadpole shrimp or a shield shrimp. So what is Triops cancriformis, and what does it look like, and what does it tell us about what it takes to be the world’s oldest species? We’re talking about early creatures here. Indeed, Triops was already a good 150 million years old when T. What? That doesn’t elucidate the matter for you? The very name Triops doesn’t bring images to mind? Well, we have to expect that this ancient life form would be something pretty obscure, given that today’s better known, more charismatic animals, such lions, tigers and rhinos, were not yet a gleam in evolution’s eye when Triops made its debut. Which is why it is such a major biological accomplishment that the world’s oldest known animal species is not 10 million years old, not 50 million, not 100 million, but 220 million years old! Or at any rate, fossils of it indicate that it has not changed its look-its external morphology, as a biologist might say-in all those years. It is a force to be admired, if not actually reckoned with. A creature that does so has shown amazing adaptability and stability. Given that habitats tend to change over time, especially over millions and millions of years (ask a dinosaur), and given that genes tend to mutate whether asked to or not, it is not easy for a species to remain the same for millennium after millennium. This description is a vast simplification of a much more complex process, but for our purposes it will do. Or habitat conditions change, and a species adapts to the new conditions over time, evolving into something new. Genes mutate, physically changing a species until, viola, after enough mutations it becomes a different species altogether. So just what is the world's oldest animal species?īefore answering that question, let’s consider what it means to be an old species. How an obscure little creature has managed to survive for so long that it represents the oldest known living animal What Is the World's Oldest Known Animal Species? ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |