4 ms·

If we find one on the moon, can we know if it originates from earth?

• falsedan 7y ago
  yes because there is no water, air, or food on the moon for a suitable habitat for tardigrade reproduction
• itronitron 7y ago
  yes, these tardigrades were sent to the Moon in a rocket
• en-us 7y ago
  We can sequence its DNA and see how similar it is to the ones on Earth. If there are living organisms on the moon that share a common ancestor with Earth tardigrades then they diverged a very long time ago and their DNA will reflect that. But if their DNA is identical to those on Earth then we know they came from Earth.
  • dwiel 7y ago
    Do you know how much tardigrades DNA have changed since they first appeared on earth?
    • en-us 7y ago
      I do not know exactly how much but this is something that can be approximately quantified.
• masklinn 7y ago
  Yes: they necessarily do so. Despite the article's statement, tardigrades are not extremophiles, they can't live in extreme environments. What they can do is exist/survive in hard vacuum and other extreme environment by entering a super-hybernation mode (cryptobiosis). Furthermore while they can survive fairly long spans in extreme environments they're not actually immortal, the FOTON-M3 mission resulted in 32% mortality after 10 days in hard vacuum but protected from UV (the survival rates were much lower for those exposed to UVs).