100-million-year-old giant sperm has been discovered by scientists

Scientists believe they have discovered the oldest sperm ever recorded and it dates back around 100 million years.

Prior to this, the oldest sperm on record was around 50 million years old, discovered inside a worm cocoon from Antarctica.

The new discovery was made within Myanmarcypris hui, a newly discovered species of crustacean, which lived in the coastal and inland waters in what is now Myanmar.

Dr. Renate Matzke-Karasz, a geobiologist at Ludwig-Maximilians-Universitaet (LMU) in Munich, and her team used 3D X-ray reconstruction to analyze 39 ostracods which were trapped in a small piece of amber.

However, this was not any ordinary-sized sperm, but giant sperm, created in smaller, but larger quantities than the large amounts of small sperm typically produced by most male animals.

As per The Independent, the newly discovered sperm was inside a pair of receptacles inside the female ostracod, simply waiting for her eggs to mature for fertilization, and scientists have said that it could be the earliest example of complete insemination.

Discussing their findings, Dr. Matzke-Karasz said: "The most significant part of our story is that we can now show that using giant sperm for reproduction is something that can last long in Earth history. Previously, we were not sure if animals that ‘switched’ to using these giant sperm at a certain point in their evolutionary history are doomed to become extinct very quickly.

"After all, these are enormous costs for the animals. Large sperm must be produced, the reproductive organs are much bigger than in other species, they take up a lot of space in the animal, and mating lasts long.

"This is a lot of biological energy that must be allocated to reproduction - so you might think that this doesn't make sense from an evolutionary standpoint. But in ostracods, it seemed to work for more than 100 million years."

The doctor explained that giant sperm is extremely advantageous from an evolutionary point of view because it has a "thoroughly profitable strategy", enabling it to last longer than its smaller counterparts.