An archaeologist working on a fossil at Ischigualasto National Park in San Juan province, Argentina, April 8, 2019. -

HO / IMCN / AFP

An international team of paleontologists have discovered, trapped in a piece of amber found in Burma, the oldest fossilized sperm in the world, 100 million years old and belonging to a tiny crustacean.

The earliest known examples of fossilized sperm so far date back 17 million years, says the team of researchers led by Dr. Wang of the Chinese Academy of Sciences in an article published Wednesday in the prestigious Journal of Royal Society.

The animal in question is an ostracod, called "Myanmarcypris hui" by these scientists, a crustacean measuring less than a millimeter existing for 500 million years.

It is represented today by thousands of species living in oceans, lakes and rivers.

GIANT FOSSIL SPERM



A tiny 100-million-year-old bivalve fossil trapped in amber has been found with what's thought to be the oldest known (animal) sperm.



These critters were really packing, as the sperm is * at least * one-third of the animals' body length.https: //t.co/zdhPUWgB8x

- Josh Luke Davis 🏳️‍🌈 (@JoshLukeDavis) September 16, 2020

"Giant" spermatozoa

During the Cretaceous period (approximately -145 to -66 million years ago), these studied ostracods probably lived in the coastal waters of present-day Burma where they found themselves trapped in a heap of tree resin.

The sperm in question were found in the body of a female specimen, indicating that she must have been fertilized shortly before being trapped in the amber.

The second peculiarity of their discovery turns out that these spermatozoa are qualified as “giants”, being able to measure up to 4.6 times the size of the body of the parent male.

"This is equivalent to about 7.30 meters in a human of 1.70 m so it takes a lot of energy to produce them!"

”, Explained Renate Matzke-Karasz of the Louis-et-Maximilien University of Munich and co-author of the study.

Quality rather than quantity

This is kind of an exception here as most males in the animal world (including humans) typically produce tens of millions of tiny sperm in very large quantities.

Like some fruit flies, these ostracods thus promote the quality of their sperm rather than the quantity.

According to the researcher, the female plays an important role since her reproductive organs must be adapted to receive and store the giant sperm.

This discovery shows "that reproduction with giant sperm is not an extinct evolutionary extravaganza, but a serious long-term benefit for the survival of a species," concluded Renate Matzke-Karasz.

Planet

Peru: 10 million-year-old fossilized tree discovered in the Andes

Science

Haute-Garonne: What is this (big) human tooth discovered in a cave?

  • Planet

  • Burma

  • Paleontology

  • Animals

  • Sperm

  • Discovery