4 ms·
Deeper in the article, there's an estimate of a 19 year lifespan. So ~20k alive at any point in time, assuming a flat distribution during that 2.5B year window
by sanj 6y ago
Deeper in the article, there's an estimate of a 19 year lifespan.
So ~20k alive at any point in time, assuming a flat distribution during that 2.5B year window.
- chrisco255 6y ago20k seems unlikely low, even as a median. A population that small would be difficult to sustain for that long through variations in climate, resources, ecosystem, and evolutionary competition.
- kelnos 6y agoThey need not have been spread across the entire planet, though. 20k in a smaller area might have been fine.
- dharmab 6y agoThere is a supported theory that at one point there were 10,000 or fewer humans on the planet: https://en.wikipedia.org/wiki/Toba_catastrophe_theory#Genetic_bottleneck_in_humans https://en.wikipedia.org/wiki/Toba_catastrophe_theory#Geneti...
- chrisco255 6y agoThis claim is not that there was 20K T-rexes at one dire point in history but an average over millions of years. Humans ended up surviving that disaster, and then went on to populate the whole earth. Also side note, supervolcanoes are scary as hell.
- antisthenes 6y agoOn the contrary, for apex predators, smaller populations are easier to sustain than large populations. Especially apex predators of that size.
- chrisco255 6y agoYeah but the prey was even bigger. Have you seen brontos? Everything was bigger in that era, including plants and trees.
- antisthenes 6y agoNot sure what your comment has to do with mine. That doesn't mean the total available biomass to predators in aggregate was larger or smaller, just because some big dinosaurs existed. It doesn't even mean T-rex hunted brontosaurus frequently or at all (given the somewhat different eras), much like the modern lions don't really hunt adult elephants.