Reviving Ancient Organisms
The idea of finding preserved life is very exciting. Finding evidence of ancient life happens constantly with new fossils being uncovered frequently. Exciting discoveries can be made from these records such as dinosaur embryos which give insight into developmental evolutionary history, or human bones that can uncover unknown aspects of our history as a species (1). Finding preserved lifeforms, let alone organisms that can be revived, seems like science fiction. However, that is what was done in a laboratory collecting sediment samples in Siberia (2). The environment being sampled was known as a permafrost condition where the ground is continuously frozen for at least 2 years of time. These conditions make preservation possible for microorganisms that can thrive in extreme cold, such as bdelloid rotifers. Bdelloid rotifers are microscopic invertebrate animals that have been known to live for at least 6 to 10 years in a temperature range of 0°C to -20°C. However, this laboratory found rotifers that had survived in permafrost conditions for 24,000 years, marking the longest reported case of frozen rotifer survival. Radiocarbon dating was used to trace rotifers back to approximately 24,000 years ago and was confirmed by sequencing the actin gene from the sample. The rotifers were shown to have a normal range of motion as well as feeding activity. Rotifers reproduce asexually, meaning without the fusion of gametes, which allows them to multiply independently. Interestingly, the researchers found that the rotifers could be cultured and were found to have normal reproduction habits and could reproduce continuously. These rotifers not only help us to learn about the traits of microorganisms, it also provides us an insight into what life was like 24,000 years ago.
References:
Black, R. (2021, December 30). Ten Stunning Fossil Finds of 2021. Natural History Museum of Utah. https://nhmu.utah.edu/articles/2023/06/ten-stunning-fossil-finds-2021
Lyubov Shmakova, Stas Malavin, Nataliia Iakovenko, Vishnivetskaya, T., Shain, D., Plewka, M., & Elizaveta Rivkina. (2021). A living bdelloid rotifer from 24,000-year-old Arctic permafrost. CB/Current Biology, 31(11), R712–R713. https://doi.org/10.1016/j.cub.2021.04.077