There is a counterargument to claims 6 and 7: there is only one known warm-blooded species with longer lifespan than humans (the bowhead whale), and it is large and has slow metabolism for a mammal. In contrast, there are plenty of cold-blooded long-lived species. So, it is entirely plausible that humans live about as long as possible for given metabolic level.
Also, note point 5 - we expect that evolution will build us to be robust enough to survive only to the point where intrinsic and extrinsic causes of death are balanced out. So a viable alternative explanation is that humans and bowhead whales are two animals that are particularly resistant to extrinsic causes of death, which makes some sense in both cases.
Whether or not this hypothesis is correct is uncertain and may be context-dependent, and I haven’t delved into the literature on this specific point enough to give any kind of authoritative opinion.
On the other hand, my understanding of the warm-blooded naked mole rat in captivity is that it doesn’t show clear signs of increasing mortality over time. We haven’t kept enough naked mole rats for long enough to see how long that lasts or whether that result is robust. But we should care at least as much about increasing rates of mortality over time—which is what it conventionally means to “age” and is captured in the concept of “healthspan”—as we care about lifespan.
Edit: I’m wrong! Naked mole rats are basically cold blooded.
There is a counterargument to claims 6 and 7: there is only one known warm-blooded species with longer lifespan than humans (the bowhead whale), and it is large and has slow metabolism for a mammal. In contrast, there are plenty of cold-blooded long-lived species. So, it is entirely plausible that humans live about as long as possible for given metabolic level.
Also, note point 5 - we expect that evolution will build us to be robust enough to survive only to the point where intrinsic and extrinsic causes of death are balanced out. So a viable alternative explanation is that humans and bowhead whales are two animals that are particularly resistant to extrinsic causes of death, which makes some sense in both cases.
Whether or not this hypothesis is correct is uncertain and may be context-dependent, and I haven’t delved into the literature on this specific point enough to give any kind of authoritative opinion.
On the other hand, my understanding of the warm-blooded naked mole rat in captivity is that it doesn’t show clear signs of increasing mortality over time. We haven’t kept enough naked mole rats for long enough to see how long that lasts or whether that result is robust. But we should care at least as much about increasing rates of mortality over time—which is what it conventionally means to “age” and is captured in the concept of “healthspan”—as we care about lifespan.
Edit: I’m wrong! Naked mole rats are basically cold blooded.