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Earlier quoted context omitted.
Or maybe that physican of the Chinese emperor was right that mercury is the key to immortality?
Wait, is it? The FDA lied about masks, and bleach, and now mercury? Do you know where I can get some?
Earlier quoted context omitted.
Selection bias ~= natural selection. If bigmouth buffalo procreate for more years because they live longer with stronger immune systems, then they will eventually make up the majority of the population.
So long as they remain capable of reproduction in those later years
Maybe healthier older fish protect their offspring more effectively.
That is beyond amazing to me. As a layperson in biology related stuff, I'd like to ask: How do scientists estimate the age of non-human animals?
"The otolith analysis revealed that about 90 percent of Apache Lake’s buffalofishes were more than 85 years old". That sounds very fishy. Perhaps they just have some sort of genetic code that make them create those new layers of calcium carbonate structures more often than once a year.
So hopefully otolith aging has been validated for this species in particular or at least a closely related one, but if not it's more likely than not reasonably reliable.
As for the population dynamics, it's not actually necessarily that strange. For many species, mortality occurs almost entirely in the early life history. Once fish escape that period, they are very unlikely to die. This can take in exactly this kind of dynamic were very few young fish are alive at any one point and most of the extent fish are very old.
Earlier quoted context omitted.
So long as they remain capable of reproduction in those later years
Is that so? I thought it’s enough if they provide an advantage for their genes. Maybe healthier older fish protect their offspring more effectively.
I’ve heard of territory defense helping with fish, but no idea about the fish mentioned specifically.
Also to the previous comment, I think there’s already a fair bit of evidence that older larger fish do continue to breed, (hence throwing back the bigger fish breeders).
But if they stop breeding, and there is no kin selection; then yes, natural selection wouldn’t play a role.
This reminds me of "The Fable of the Dragon-Tyrant" by Nick Bostrom [1]. Senescence is engraved in our brains as universal. Just like our expectation about health which should deteriorate overtime.
> These calcium carbonate structures, which allow fish to hear and sense vibrations in the water, form a new layer each year that can be read somewhat like tree rings. Each time I read dating method like these, I wonder how stable these method are. Sure they are sensitive to water temperature, right? We have not-so-long-term climate changes, periodic solar storms and irregular volcano eruption.. All these are affect…
That getting said, climate change and other things are unlikely to overwhelm the seasonal cycles. Yes, it's gotten warmer, but it's still colder in winter.
It's also preferable to have validation for a given taxa, but i wouldn't expect that particular worry to be the failure more.
It's not clear from the article but animals can generally live quite a bit longer than you'd expect if they continue to grow for their entire life, which is true for some types of fish. Gunk that builds up inside or between cells gets redistributed over larger areas, as do cells that become senescent. And larger size means more space for memory T cells. Those are only some aspects of aging of course.
Don't cancer rates tend to correlate positively with number of cells?
That is beyond amazing to me. As a layperson in biology related stuff, I'd like to ask: How do scientists estimate the age of non-human animals?
These structured grow with the fish and seasonal changes in growth rate cause lighter and darker alternating bands, similar to tree rings. When prepared correctly, these bands can be viewed and counted inter s microscope.
Similar methods are used in fin rays and spines, scales, and vertebrae, although otoliths are generally considered the gold standard
It's not clear from the article but animals can generally live quite a bit longer than you'd expect if they continue to grow for their entire life, which is true for some types of fish. Gunk that builds up inside or between cells gets redistributed over larger areas, as do cells that become senescent. And larger size means more space for memory T cells. Those are only some aspects of aging of course.