In a quest to learn more about the history of our planet’s extinct creatures, a group of international scientists set out on a mission to find ancient DNA which was still intact. Their mission led them to a well-preserved freeze-dried Woolly Mammoth skin sample, excavated in northeastern Siberbia in 2018. An incredible finding that allowed the researchers to examine the Woolly Mammoths’ complete DNA like never before.
The Woolly Mammoth
The extinct Woolly Mammoth was about the same size as the African Elephants we know and love today. These ancient creatures were well adapted to the cold environments they were forced to endure, with thick fur coats varying in color from light to dark. Even their ears and tails were shorter and smaller to minimize their exposure to frostbite and heat loss. And just like their descendants today, the Woolly Mammoths survived on a herbivore diet.
Ancient Hide
During their quest to uncover the secrets kept in ancient DNA, the team of scientists finally got their hands on a piece of skin from a female woolly mammoth’s head that lived 52,000 years ago. Her skin was naturally freeze-dried (cooled and dehydrated) to change into a glass-like structure, preserving her genome shapes in a layer of permafrost for millennia. This glass-like structure is called chromoglass, which kept this woolly mammoth’s DNA pieces from drifting apart. Exciting scientists in the field everywhere!
Reconstruction
Until this discovery, ancient DNA had only been found in fragments which limited what information researchers and scientists could gain. However, this freeze-dried gift from the past changed the game completely. Scientists used this rare, yet wonderful, Woolly Mammoth DNA sample to reconstruct the genome in 3D to bring new information to light regarding the life of this extinct creature.
But, How?
Scientists use the Hi-C method to have a look at the 3D structure of DNA from fresh, intact samples. This method, however, was not working for ancient samples. Luckily, the clever team of scientists invented a different version of the method, called PaleoHi-C which helped them analyze the genes of this extinct mammal.
For The Love Of Knowledge
An understanding of ancient creatures’ genomes (their complete set of DNA) is needed to understand which genes were active in which parts of their bodies. And through this method, scientists can create a 3D map showing how different parts of ancient genomes interacted, helping them understand more about the biology of long-extinct species, like the woolly mammoth!
Locked In
This exceptionally well-preserved DNA sample’s chromosomes were also locked in place, which means that for the first time ever, scientists were able to determine how many chromosomes these animals had! Enabling them to find out that Woolly Mammoths had 28 pairs of chromosomes – the same as elephants today. The sample analyses also showed that Woolly Mammoths and elephants share the same basic chromosome structure, confirming the belief that elephants are the closest living relatives to these ancient creatures.
Further Findings
The glass-like DNA structure also allowed scientists to determine which genes of the woolly mammoths were turned on (instructing cells to perform specific functions) or turned off (not providing these instructions). The team found 395 genes turned on in elephants, but not mammoths, and 425 turned on in mammoths but not elephants.
Hairy
Finding these genes helped explain why woolly mammoths had certain features. One of the genes turned on in elephants but not in mammoths, was the gene that controls skin and hair growth. For instance, if this gene is switched off in humans, it will cause thick, long eyelashes and extreme hair growth – possibly making this gene the reason woolly mammoths were woolly!
Last Thoughts
Science and the constant development in the field is amazing! It is mind-boggling to think, that from just one tiny piece of (perfectly) preserved DNA, so much could be determined from an animal that hasn’t walked the earth in hundreds of years. With this new method, we hope that many more such learnings are to come.
Please send any feedback to feedback@animalsaroundtheglobe.com
- Cat Photographer Shares His “Favorite Project Ever” - September 13, 2024
- Man’s Life Mission Helps Hundreds of Street Dogs in Thailand - September 13, 2024
- Super Cat Saves Human Brother From Dog Attack In California - September 13, 2024