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I've always wondered how coral reefs stuck around for hundreds of millions of years if they're so fragile and prone to death without recovery.
by ummonk 7y ago
I've always wondered how coral reefs stuck around for hundreds of millions of years if they're so fragile and prone to death without recovery.
- garmaine 7y agoAlso, the Earth's climate has been much, much warmer than today in the past.
- hannasanarion 7y agoyes, but it usually changes over the course of thousands of years, not tens of years. In the past, coral migrated north and south to stay in the optimal temperature. There's not enough time for that at the scale of anthropogenic climate change.
- masklinn 7y ago> yes, but it usually changes over the course of thousands of years The scale we're observing right now is the stuff of millions of years of change, or massive extinction events.
- hannasanarion 7y agoYeah, exactly. If the change happens as fast as it is happening, you get a mass extinction. If the change happens over thousands of years, biomes have time to migrate. Using the xkcd timeline as a guide, the temperature change in the last 120 years is about the size of the temperature change between 11,000 and 9,000 BC, which was only mildly disruptive to global ecology.
- garmaine 7y agoSo move the coral.
- pvaldes 7y agoIs a possibility
- masklinn 7y agoA big difference is that has not usually happened at such a high rate of change. "Geological" warming normally happens over tens of millions of years, not tens of decades (e.g. Cambrian's 55MA was a warming period from current-ish to early ordovician greenhouse). More rapid changes have been massive extinction events (e.g. O-S).
- kaybe 7y agoWhat is actually quite fast is the change from ice age to interglacial: hundreds to thousands of years in temperatures from Antarctica. It is not quite clear yet how that happens. https://en.wikipedia.org/wiki/File:Ice_Age_Temperature.png https://en.wikipedia.org/wiki/File:Ice_Age_Temperature.png
- lazyjones 7y agoPerhaps they like warmth and will spread towards the poles from where they are now - the hottest waters. https://oceanservice.noaa.gov/facts/coralwaters.html https://oceanservice.noaa.gov/facts/coralwaters.html The IPCC doom predictions simply make no sense to me given that large parts of the oceans are currently too cold for corals (by 10+ K).
- Loughla 7y agoI think it's about the speed of adaptation or even migration, for that matter. If they had thousands or tens of thousands of years to adapt, sure. But it's more in the 50-100 year range.
- kls 7y agoSee my post above 50 years to regenerate is the only data we have and in that time the Bikini Atolls reef is nothing short of a success story given the fact that it was nuked into oblivion less than 100 years ago.
- masklinn 7y ago> The IPCC doom predictions simply make no sense to me given that large parts of the oceans are currently too cold for corals (by 10+ K). Coral reefs don't get built over two weeks, or even two centuries. Furthermore warm-water corals need sunlight, and proper depths.
- kls 7y agoYou are right it takes about 50 years given the only data we have on how fast they regenerate. The Bikini Atolls being the only data point we have.
- masklinn 7y agoBecause rate of change is a factor. Even slow organisms are able to move around / adapt (unconsciously obviously, and mostly if widespread, and sheer luck is a factor) to slow rates of change. Or they can repopulate their old niche afterwards (over hundreds of generations) from populations which avoided or were protected from the disaster e.g. cold-water corals. The current rate of change is not slow, we're doing over a handful of generations what would naturally take thousands or tens of thousands of years.
- slavik81 7y agoThe current Great Barrier Reef is 8,000 years old, having regrown after the last ice age. There's been a reef there for 500,000 years, but it's been destroyed multiple times. Of course, the time scales involved are quite long. Recovery is thought to have taken hundreds of years, if not thousands. And the process only starts after conditions improve. See Also: https://www.sciencemag.org/news/2018/05/great-barrier-reef-has-had-five-near-death-experiences-past-30000-years https://www.sciencemag.org/news/2018/05/great-barrier-reef-h...
- kls 7y agoThat is strange given how fast the Bikini Atoll reefs regenerated themselves, even after being nuked.