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Fossil hints that Jurassic mammals lived slow and died old
- tamimio 2y agohttps://archive.is/ZKg4B https://archive.is/ZKg4B
- tambourine_man 2y ago[dead]
- BWStearns 2y agoI wonder if the harsh post impact environment selected for small, short lived creatures due to the lower caloric energy requirements, and faster genetic iteration speed respectively. If your environment is particularly hostile with low resources then taking many small bets quickly might be the favored play.
- StanislavPetrov 2y agoIt would be interesting to know what the climate was too. If these animals hibernated or slowed their metabolism during cold periods it would help explain their longevity.
- CoolGuySteve 2y agoScotland was around 35 degrees latitude and the Jurassic period was fairly warm compared to now (tropical plants are found up to 60 degrees latitude) so it’s unlikely there was a winter to hibernate through. However there was significantly more oxygen in the atmosphere back then. There could be a metabolic component related to that since absorbing O2 was probably easier.
- fhars 2y agoWe have no idea when that transition happened, though, and if it is related to the impact. The time from when these animals lived in the Jurassic to the impact at the end of the Cretaceous is considerably longer than the time from the impact until today, much could have happened inbewteen.
- cworsley4 2y ago“Fossils”
- layer8 2y agoYeah, I was reading it as the VCS for a moment there.
- plutomeetsyou 2y agoIs it possible due to the more oxygen rich environment during the jurassic era?
- K0balt 2y agoIt seems logical that a faster Metabolism, quicker to reach reproductive viability organism would frequently outcompete slower variants In the same biome niche.
- vanderZwan 2y agoNot really, since a faster metabolism requires more energy upkeep, and food scarcity has always been one of the biggest selection criteria in nature.
- K0balt 2y agoFrequently.
- vanderZwan 2y agoEh, no, that qualifier does not fix your argument, because it's not a caveat. Natural selection by definition works on which trait outcompetes the other one most frequently, it's a statistical process. There is a reason life works on a sigmoid growth curve and not an exponential growth one.
- K0balt 2y agoI think maybe people thought I was asserting that it was generally a better solution… I was not. But fast reproduction is hardly a rare trait in nature. An ideal solution would be variable rate metabolism, and we see that in species capable of hibernation. Of course slow metabolisms have advantages in resource constrained environments.
- KineticLensman 2y agoMetabolically slow ambush predators (some snakes, spiders, etc) can also do extremely well in a given niche, and some of these strategies are ancient.
- 2y ago
- cvaidya1986 2y agoMammals were the startups of the Jurassic era ( just survive and you might end up being huge later )