6 ms·
Mammals have adapted to adverse conditions before. However, the current rate of change is unprecedented. Evolution does not happen in one or two generations.
by juujian 3y ago
Mammals have adapted to adverse conditions before. However, the current rate of change is unprecedented. Evolution does not happen in one or two generations.
- fsckboy 3y agowhen evolutions happen, they do happen in one generation, that's where new clades are formed
- 8ytecoder 3y agoA mutation happens in one individual in one generation. Evolution happens when that mutation propagates through the population by reproduction. That itself takes many generations. Not to mention the fact that the mutation needs to be both advantageous and be recognized as such.
- lazide 3y agoEvolutionary bottle neck events don’t work in such a polite and calm fashion, and there have been many of them. What happens is 90% of the population (or often more like 99.999%!) that don’t already happen to be carrying an advantageous mutation perish. Sometimes the whole species goes extinct if there is no such mutation already there. The remainder, if there are any, then don’t have to worry about as much competition, and rapidly reproduce to fill the now mostly empty niche.
- szundi 3y agoSadly the gene has to give some advantage to its bearer to actually spread in the population. With only future benefits, i does not spread.
- thaumasiotes 3y ago> Evolution happens when that mutation propagates through the population by reproduction. Evolution happens when the distribution of genes in one generation differs from the distribution of genes in the previous generation. It happens every generation without fail.
- whyenot 3y agoA significant number of mammals have generations every year (or less).
- firecall 3y agoThere are observed cases of very rapid adaptations occurring.
- whyenot 3y agoYes, there are annual plants that evolve significant adaptations to avoid water loss within five generations (5 years), in response to drought. Things like having smaller flowers, flowering earlier in the spring, and smaller leaves. Many plants also have a lot of phenoplasticity that allows them to adapt without genetic (evolutionary) change.
- dataflow 3y agoGlad to hear we can carry on as usual without worrying about completely destroying life on the planet.
- szundi 3y agoYes, the planet and life will survive us
- hibernator149 3y agoIn the last couple of years I've been thinking more often about a Venus scenario where life does not survive. We are just hoping that life will find a new equilibrium in the next couple million years like it has in the past. But if temperatures rise too fast, the planet will just get cooked before enough CO2 will be sequestered. The great filter is still in front of us.
- runeofdoom 3y agoI've sometimes wondered if Venus' runaway greenhouse had been caused (presumably unintentionally) by intelligent Venusians in the distant past, how could we find out? What bio- or techno-signatures would we still be able to find? And what possible such signatures would be easiest to look for given the inhospitable conditions?
- hifycycyv 3y ago[dead]
- Qem 3y agoThe next supercontinent is expected to form in about 250 million years. Plenty of time for mammals to evolve, if we don't wipe all the other first.
- 6sebulba 3y ago[dead]
- edgyquant 3y agoTurning to cold blooded probably doesn’t, but evolution most certainly occurs in a generation. It may mean all but a few who manage to survive die but those are the ancestors of the new species
- szundi 3y agoNo, mutation or recombination does happen in one generation. Then it has to spread and that needs quite a lot of generations. Mice can have a successful gene spread out in 20-30 years in a local population, humans need a thousand years for the same.
- omeid2 3y agoThat argument is only true for humans and other "long" lived species. For example look at at how much canines have evolved in the same time span that homosapiens have stayed relatively "static". Long and static, in very very relative terms, of course.
- kaba0 3y agoIf you mean dogs — they were bred by humans for that purpose, that operates very distinctly from “raw” evolution. The latter is not particularly fast at adopting, it survives mostly by having a huge variety in the first place, and in an adverse environment some will survive, quickly growing in numbers due to the abundance of resources left behind by other former competitors. But that only works if the adversity is not too extreme, at least in case of more complex life forms (plants, animals).
- dclowd9901 3y agoDoes that mean it can’t? I know at least a few people who are especially sensitive to heat and cold. It seems likely there are folks out there who could continue to survive environmental changes given our population, just not as many as currently exist.
- samus 3y agoOur population is as high as it currently is because of technology. Without technology, it is not possible to sustain and feed people in cities.
- simonh 3y agoOr in fact in most habitats humans have colonised within the last hundred thousand years. People forget that fire, spears, clothing, constructed shelters, etc are technology.
- deleted 3y ago[deleted]
- jemmyw 3y agoThis prediction isn't about climate change, it's about the formation of a new super continent. Because it'll be such a large landmass, and the energy from the sun increases by about 1% every 100 million years, the inner parts of this continent are predicted to be too hot to support most life as we currently know it. Of course, who can really say what will happen / evolve / be there by that time anyway?
- deleted 3y ago[deleted]
- hnfong 3y agoNot sure this makes sense unless that super hot and dry inner landmass doesn't look like deserts we have today. Desert animals will thrive there, but I doubt most mammals will evolve to adapt to that environment...
- jmartrican 3y agoA large asteroid hit the Earth and lead to rapid unprecedented change. Yet here we are.