alt Hacker NewsThis is an interesting way to think about plants and animals.
I'm finding it surprisingly hard to find sources for known age of species - is that information collected somewhere? Or is it something we often just don't know because of how sparse the fossil record is?
Wondering because of trying to look up the age of fern species I do eat (no cinnamon fern near me) and I can't find out.
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> I'm finding it surprisingly hard to find sources for known age of species - is that information collected somewhere? Or is it something we often just don't know because of how sparse the fossil record is?
It depends on what you mean by the age of the species. You can find the oldest known fossil occurrence at the Paleobiology Database [1] and the divergence time from molecular phylogenies via TimeTree [2].
It's pretty tricky to find out, yeah. And new evidence is coming in all the time. All the methods are either floors (a fossil at X date proves a species existed then, but lack of fossils found yet might be inconclusive) or estimates (like molecular clock techniques). Dating fossils themselves (or rather the rocks they're buried in) isn't always easy or possible. For more out-of-the-way species, if anyone has bothered trying to figure out the age it's likely buried in scientific sources that are tricky for novices to find or search, and maybe under debate.
That's because when something becomes a new species is a surprisingly difficult and contentious debate in biology.
That's simply due to the nature of evolution. It's nearly impossible to look at one past generation of chicken to the next to figure out when the ancestor was no longer a chicken. Yet, go back far enough and you'll find T-Rexes in the mix.
Every generation is a new missing link. It's an extremely fuzzy process.