Tamreen: for a sense of scale, the last time this happened plants evolved not a specific species or something. Literally just Plants

for a sense of scale, the last time this happened plants evolved not a specific species or something. Literally just Plants

wake up babe new* endosymbiotic organelle just dropped. They confirmed it's more than just symbiosis when they saw it absorbing whole proteins from the host! *100 million years old, but that's new compared to billions-years old mitochondria and chloroplasts

Scientists discover first nitrogen-fixing organellenews.ucsc.edu In two recent papers, an international team led by UC Santa Cruz scientists describe the first known nitrogen-fixing organelle within a eukaryotic cell. The organelle is the fourth example in history ...

Not quite: Mixotricha paradoxa, a gut protozoan in termites that digests cellulose for them, it *once* had mitochondria but gave them up in favor of a new endosymbiont. It has 5 different genomes due to having *multiple* endosymbionts cooperating. en.wikipedia.org/wiki/Mixotri...

Mixotricha paradoxa - Wikipediaen.wikipedia.org

so as I understand the difference is that the endosymbionts in M. paradoxa are still considered separate organisms, not organelles. The nitrogen fixing plastids here have become full organelles - they rely on the host cell for proteins and have the same metabolic rate

Article says ectosymbionts, so yes.

How about apicoplasts in Apicomplexan parasites? cryptosporidia, malaria, toxoplasma? Apicoplasts are *secondary* symbiotes. A cyanobacteria assimilated an algae, and then that resulting symbiotic organism was assimilated by another.

true I think secondary endosymbiosis has happened a few times so this'd be a relatively rare instance of primary endosymbiosis. It's been a while since a regular bacteria turned into a new organelle

Whoa

Probably completely misremembering but didn’t that lead to the largest extinction event in history as the proto-plants start pumping out oxygen which choked almost all the then existing living organisms?

sorta related but what you mentioned happened when cyanobacteria first evolved photosynthesis and started oxygenating the world (about 2 billion years ago). 1 billion years ago, a completely different cell absorbed a cyanobacteria and turned it into an organelle over time

So I, personally, shouldn’t be too worried about this? Cool, cool…

nah no major new metabolic chemistry, just a new rearranging of some existing ones

so a new kingdom?

nah still plants for now, just ones that can fix nitrogen from the air themselves

Not even plants exactly! The Archaeplastida, the OG eukaryotic algae, which would later give rise to plants (and also to other groups of algae which stole their chloroplasts). This happened somewhere around 1.6 billion years ago. Land plants are maybe 0.5 billion years old, slightly less probably.

📌

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