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A comment on Tiny fern has the largest genome of any organism on Earth. Parent comment

Re:Tiny fern has the largest genome of any organism on Earth by throwup238 on Saturday June 08, 2024 @01:29PM (#40619034)
It's an active area of research but there's no consensus on why this happens other than hand wavy evolutionary biology stuff. The most interesting mechanism is paleopolyploidy [1] where the whole genome of the organism is doubled due to hybridization or DNA replication errors and from that point on the duplicates start diverging. It has occurred at least once in most flowering plants and it must have happened several times with this fern. Normally after this kind of event, the genome is paired down and duplicate genes are "silenced" in a process called diploidization [2] but if there are a bunch of transposable element, they might differentiate the copies enough to keep them before the process completes.

[1] https://en.wikipedia.org/wiki/Paleopolyploidy

[2] https://en.wikipedia.org/wiki/Diploidization

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Re:Tiny fern has the largest genome of any organism on Earth by PartiallyTyped on Saturday June 08, 2024 @04:54PM (#40620119)
There’s a recent veritasium video on jumping spiders. Turns out some of them evolved red colour eyesight in multiple independent ways, one example involves replicating a green colour vision gene and then mutation, another one adding a filter on top of green colour receptors, forcing neurons to activate on red instead!
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Re:Tiny fern has the largest genome of any organism on Earth by bee_rider on Saturday June 08, 2024 @08:24PM (#40621058)
Well it makes perfect sense, after all you have to water plants. So, they can’t be DRY.
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Re:Tiny fern has the largest genome of any organism on Earth by Optimal_Persona on Monday June 10, 2024 @06:15PM (#40639830)
Thanks, I need a LOL moment today and you gave it to me! Good thing I didn't soil myself in the process...
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Re:Tiny fern has the largest genome of any organism on Earth by colinflane on Saturday June 08, 2024 @11:09PM (#40621724)
Unimportant, but "pared" down, not "paired".
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Re:Tiny fern has the largest genome of any organism on Earth by tonetegeatinst on Sunday June 09, 2024 @04:19AM (#40622843)
Life...uhhh....finds a way

- Jurassic Park

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Re:Tiny fern has the largest genome of any organism on Earth by gww on Sunday June 09, 2024 @08:27AM (#40623976)
It is common for human cancers to be polyploid after accumulate whole genome doublings (WGD), where a tumour cells goes from being approximately diploid to tetraploid. Different tumour types have higher rates of WGD, for example, glioblastoma, ovarian cancer, and pancreatic adenocarcinoma. But what usually happens is that the tumour loses parts of the doubled genome to reach a ploidy (average copy number across the genome) of 3-4ish.
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Re:Tiny fern has the largest genome of any organism on Earth by 7373737373 on Sunday June 09, 2024 @02:09PM (#40626299)
> there's no consensus on why this happens other than hand wavy evolutionary biology stuff

This reminds me of a comment about chess - there may be certain abstractions, lines/strategic patterns with meaningful relations "in the big", but in the small, like with endgame tablebases, small differences in state have an effect on the outcome of the system that is difficult to explain/predict because it seems to be random.

Like looking into an extremely compact fractal phase space instead of more predictable/seemingly geometrical ones.

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