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Where does the energy come from to lift water by osmosis?
  • As others have stated, water in trees gets up thanks to two processes. The first is indeed capillary action. The tubes carrying the water are rather thin, and it clings to the sides of it. But this is a rather small part of the total energy carrying the water. The main mechanism is a negative pressure inside the vascular system of the tree. Basically, tree leaves sweat water all the time (more or less depending on temperature). The water leaving the tree kind of sucks up the water following inside the vessels (this is a simplification to not go into the physics behind). In some larger trees, the negative pressure inside the vascular system can be exceptionally strong, requiring exceptional strength of the tree's components.

  • Crowd Cheers as Convicted Rapist is Eliminated in Olympic Beach Volleyball
  • I am European and heavily against punitive justice. But I think one year of prison for a crime almost universally considered among the worst is not enough for rehabilitation, and I find this opinion validated by the lack of understanding or even remorse shown by the guy in public statements

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    Aidez-moi à faire avancer ce combat : Emmanuel Macron doit demander la libération de Paul Watson !
  • Bonjour, C'est une mauvaise lecture, heureusement 70% des espèces n'ont pas disparu, les populations pour beaucoup d'espèces ont chutés de 70%, ce qui est déjà largement assez dramatique, avec effectivement beaucoup de conséquences comme les zoonoses (passages de virus de la faune sauvage vers l'humain). Pour l'anecdote, 70% d'espèces véritablement éteintes, c'est l'estimation pour la crise crétacé-tertiaire s'il y a 66 millions d'années, avec son combo météorite-volcanisme-changement climatique !

  • Professional Scientists of Lemmy: What is your field of study's, most complex unanswered question?
  • The diapsid part is very likely indeed, as fossil skulls of early stem turtles do show some temporal openings ( https://www.annualreviews.org/content/journals/10.1146/annurev-ecolsys-110218-024746 ) The point is more where do they nest within Diapsida, more closely to the Lepidosauromorpha, or to the Archosauromorpha, and where precisely if within one of those clades. The point is that can't quite be proven using only extant species, whether by DNA or morphological evidence. And concerning ML, the methodology is often criticised, not because it's bad, but because it's opaque and thus it is difficult to justify and understand as a process

  • Professional Scientists of Lemmy: What is your field of study's, most complex unanswered question?
  • In phylogeny, genomic is just another tool. The point is that turtles are os course animals, but they do branch off of different reptile groups if you look at morphological evidence (which includes fossil data) or at molecular (genetic) evidence (which only includes extant species). This is not something frequent, as usually molecular evidence tends to strengthen previous morphologically established evolutionary relationships. And even though molecularists are more numerous today, their methods are neither better or worse than anatomy.

    Phylogeny is not as straightforward as some people make it seem, and especially molecular phylogeny tends to rely on abstract concepts that can't always be backed up by biological evidence (I'm not saying it's wrong, it's very often very good, juste that a lot of people doing it do not understand the way it works, and thus can't examine the process critically).

    And so turtles' origin are still very much an active debate!

  • Professional Scientists of Lemmy: What is your field of study's, most complex unanswered question?
  • I feel inappropriate near all the very universal questions here, but as a paleontologist specialised in some reptilian groups, the question would probably be "where the fuck do turtles come from?!" The thing is that fossil evidence points to different answers when compared to genetic evidence, and thez separated long enough from other extant groups that we keep on having new "definitive" answers every year

  • Gabriel Attal becomes France’s youngest and first openly gay prime minister
  • He was Education minister before this, despite never setting foot in a public school, and heavily criticised protesters during the very unpopular pension reform while he was already a millionaire at 25 even though he never worked a day in his life. But hey, nice for us that he's young and openly gay !

  • New Zealand scraps world-first smoking ‘generation ban’ to fund tax cuts
  • If you do that, then you should also forfeit your right to use publicly funded hospitals that already struggle enough with people suffering of conditions they did not ask for voluntarily. Smoking is not just a cost for your body, but for society as a whole, hence the justification in a ban

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    *Permanently Deleted*
  • Yes, and as someone who is probably close to a 5yo's knowledge on the topic, I don't know anything (or close to that) on either programming or other parts of being "tech savvy". Thus me saying that coming on the ELI5 community and saying "yeah I actually want a very much not 5yo answer type" is not the spirit, I'd much rather like first basic answers, and eventually other comments going more in-depth, like we see in the majority of posts here

  • Sarcosuchus imperator, our community's banner !

    Sarcosuchus was one of the largest crocodylomorph to ever live, around 110 million years ago. This incredible specimen is exposed in Paris, at the Muséum national d'Histoire naturelle, in the Paleontology gallery. Some bones are artificial and can be recognized by the uniform grey color (like most of the limbs), but a lot of other are directly from the specimen, like almost all of the skull ! Picture from Wikipedia, by Shadowgate from Novara, ITALY

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    Crocodilia on Wikipedia

    As the start of this community, why not learn about the group including all extant crocodiles ?

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    InitialsDiceBearhttps://github.com/dicebear/dicebearhttps://creativecommons.org/publicdomain/zero/1.0/„Initials” (https://github.com/dicebear/dicebear) by „DiceBear”, licensed under „CC0 1.0” (https://creativecommons.org/publicdomain/zero/1.0/)TH
    TheMetaleek @sh.itjust.works
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