The soft body of worms remain rarely preserved as fossils. A paleontological record, there is now yet: In a fossil the oldest known sperm were found.
The oldest sperm in the world are 50 million years old. They were discovered in fossilized worm cocoon of a belt in Antarctica. Your Fund presents the international research group led by Benjamin Bomfleur from the Natural History Museum in Stockholm in the journal’ Biology Letters’ of the British Royal Society.
The researchers had in the electron microscope, the inside of only 1.5 millimeters long fragment of a belt worm -Kokons investigated. They discovered various inclusions, for example elongated screwed threads and grainy fingers with peitschenartigem tail. There are items typical belt worm sperm, say Bomfleur and colleagues.
Genome Research Limited Known representatives of the belt worms ( Clitellata ) include earthworms and leeches. On a slightly thickened body section – the so-called belt – but during mating a mucus ring with eggs and sperm from. In this the eggs are then fertilized. The result is a more resistant cocoon, filled with a protein-rich liquid and thus ensures the supply of larvae.
During the soft worms and their short-lived sperm barely fossils are preserved, can be found again and again such fossilized cocoons. The trapped in the cocoon wall sperm are a very special treasure, the researchers explained. He comes from marine deposits on the Antarctic Peninsula, which are known for their fossil wealth.
In the animal kingdom with about 40 million years previously oldest known sperm came from a trapped in amber springtail.