Earthworms were all but wiped out in North America during the last ice age. The earthworms in North American soil today are almost all European. They're still spreading out and moving North in Canada.
Mindblowing Implication:
Prior to the introduction of European earthworms, dead leaves and other detritus just sat on the surface and accumulated until it was several feet deep in forests. Native plants often took advantage of this slowly decomposing source of nutrients. Earthworms break that detritus down into humus much faster, often starving native ground-cover plants and feeding invasive species. We're still watching a massive change to ecology, that started at the time of European contact, slowly unfold.
Another interesting thing I got to know recently is that during the Carboniferous period, trees would grow old and fall but not rot since the bacteria and fungi had not yet evolved the enzymes to digest them [0]:
11,000 years isn't millions of years, and there are hundreds of native North American species of earthworms. The invasive species are a problem, but detritus accumulation is not something that North American flora evolved with until an eyeblink's worth of evolutionary time.
Hasn't it been shown that evolution can occur over 1000's of years, but of course over millions it would diverge even further.
Can something that was only here 11,000's still qualify as native?
It is pretty amazing how things are still evolving.
Like the comment below about how the European Worms are still migrating, so the entire ecosystem is still adapting and changing.
So we are seeing evolution in progress, and maybe 10,000 years from now, someone will be arguing that the European worms are more 'native', and these new Mars worms brought back from the colonies are really invasive.
Evolution is a continuous process, so yes, there's some degree of change every generation. It is also true that 11,000 years is a very short time on the scale of speciation.
It's probably most useful to think of worms coming back in to the soil as another stage of progression, just like the stages of a forest returning after a fire, volcano or the like.
That is mind blowing. New Zealand where I live, an extremely remote island, has over 200 species of earthworm most of which are native and only found in NZ.
Only about 15% of NZ was covered by ice during the ice age.
You make an interesting point about the terms "native" and "invasive." The lines between what's considered native or foreign in nature and in demographics can be blurry, especially over long periods of time.
The earthworm story highlights how nature simply evolves, and labeling things as native or invasive can mirror some societal attitudes. These words can carry some deep biases.
Over enough time, the invasives become natives. After all, no one seriously argues that the Anglo-Saxons are invasive to England and that Britain should be given back to the Welsh.
I was a bit suspicious of the claim, but found evidence that this might actually be the case. Here's a page focused on research related to non-native earthworms in North America that seems like a good start: https://www.nyisri.org/2016/09/underground-invaders-impacts-...
I love that a guy as brilliant as Darwin spent time cutting paper into triangles to give to worms to see how they stuffed it into their burrows.
My favorite earth worm fact is you have approximately one hundred million worms worth of energy in your body *(the sum of the stored energy in all your mitochondria).[1]
There's something fucky about that. He's comparing the total amount of electrical potential energy in a human body to the amount of chemical energy available to a living worm's metabolism. A typical human has about one hundred thousand times the mass of a typical earthworm, so this guy is saying human flesh is one thousand times more energy-dense than worm flesh. Horseshit.
Edit: That whole article is riddled with errors. For example, he states 220mm^2 is 88% the surface area of a dime when in fact it is 87% of the surface area of one face of a dime.
(Mitochondria) "The electron and proton
transfers of chemiosmotic energy coupling generate a transmembrane
potential of 150–200 mV over the membrane (~5 nm across), giving a
field strength of about 30 million volt per metre, equal to that discharged
by a bolt of lightning."
Nick Lane and William Martin obviously don't talk about any directly obtainable energy. That number just can't be compared to the
"Available energy reserves (Ea)" "measured by quantifying the total lipid, protein, and carbohydrate content" from the
Also note: worms have mitochondria in their cells too.
Conclusion: "metabolism of a person and a worm" article is a good example of false claims which could be found on the internet, and the author, if he wants to help, should delete all the claims from it and put a note that what was on the page was false.
Maybe that comparison is wrong, i.e. different kinds of energy compared for humans and earthworms? For the later, if I understand correctly, the linked paper measures an equivalent of "how much energy one gets by burning the stuff from which an earthworm is made". For the former, it's something else: "total stored charge in all mitochondria membranes".
I'd expect that comparing the same kinds of energy the ratio would be more similar to a ratio of weights of the two organisms.
And checking the actual sources(1) the original authors correctly talk about the electric potential difference (voltage) over over the ~5 nm membrane, which is "equal to" the one "discharged by a bolt of lightning." It's clearly wrong to use that for the false claim in the article of "adding up" "the stored charge in one person".
I do feel bad for how much food I eat, probably requiring several hectares to grow, compared to smaller animals which can survive by nibbling a few leaves.
> so 50 million worms colliding with 50 million anti-worms
Oh god no! If the average worm massed 10g, that's 10^9 grams of worm/anti-worm mix. Those 1000 metric tons of helminthic hitchikers would undergo total-annihilation to generate 9*10^22 Joules of energy, or 21.53 teratons of TNT.
Not only is that bigger than any nuclear bomb, it is likely way more than the yield of all nuclear bombs ever made rolled into one. This means it would be a Very Bad Day for both humans and worms on one or more continents. :P
(P.S.: Note that yield is only 1.7%-6% of estimates for the Chicxulub asteroid impact, so it is likely some worms will survive and maybe even some humans too if we don't botch handling the apocalypse.)
The humble earthworm? There are thousands of species of them!
(Wikipedia says: "Currently, over 6,000 species of terrestrial earthworms are named, as provided in a species name database, but the number of synonyms is unknown." Coincidentally, there are also about 6000 species of mammal.)
Earthworms were all but wiped out in North America during the last ice age. The earthworms in North American soil today are almost all European. They're still spreading out and moving North in Canada.
Mindblowing Implication:
Prior to the introduction of European earthworms, dead leaves and other detritus just sat on the surface and accumulated until it was several feet deep in forests. Native plants often took advantage of this slowly decomposing source of nutrients. Earthworms break that detritus down into humus much faster, often starving native ground-cover plants and feeding invasive species. We're still watching a massive change to ecology, that started at the time of European contact, slowly unfold.