Oldest Sperm Ever, Discovered in Antarctica

By Nia Brown

Updated

Image: Popular Science

Antarctica’s Fossils

Research in Antarctica has led to many intriguing discoveries: including meteorites, giant penguins, a host of dinosaur species, and evidence of forests. The islands off the Antarctic peninsula have been especially interesting to scientists. Now, a new discovery has been made on Seymour Island, the only dig site free of ice cover and where the K-T boundary, marking the end of the dinosaurs, is studied.

Oldest Sperm Discovered

Benjamin Bomfleur of the Swedish Natural History Museum and other researchers have discovered the oldest animal sperm ever. It is from some type of worm living 50 million years ago. The researchers unintentionally came upon the biological material, encased in a cocoon the Eocene era worms used as protective casing for fertilized egg cells.

Cocoons: Microbe Time Capsules

Microorganisms like this are hardly ever found preserved as fossils. In contrast to bone, the material is fragile and typically decays well before fossilization can occur. Hardened cocoons successfully encase this kind of material and various kinds of cocoon have been found from the north to south poles Bomfleur explains. They will likely continue to be found and reveal more and more about ancient organisms. Bomfleur highlights his hope to possibly find an ancient encased tardigrade, the enigmatic, ultimate-survivor creatures.

Water bear (Macrobiotus sapiens) in moss. Color enhanced scanning electron micrograph (SEM) of a water bear in its active state. Water bears (or tardigrades) are tiny invertebrates that live in aquatic and semi-aquatic habitats such as lichen and damp moss. They require water to obtain oxygen by gas exchange. In dry conditions, they can enter a cryptobiotic state of desiccation, known as a tun, to survive. In this state, water bears can survive for up to a decade. This species was found in moss samples from Croatia. It feeds on plant and animal cells. Water bears are found throughout the world, including regions of extreme temperature, such as hot springs, and extreme pressure, such as deep underwater. They can also survive high levels of radiation and the vacuum of space. Magnification: x250 when printed 10cm wide.
NASA

Sources: Popular Science, Washington Post, British Antarctic Survey
Image: Popular Science, NASA