Humans lifespan was that low since the high mortality rate the first months of life. After the first years, the expected lifespan increased dramatically. A huma

Humans lifespan was that low since the high mortality rate the first months of life. After the first years, the expected lifespan increased dramatically. A humans need a few years to be able to reproduce and those who were able to have a longer lifespan. Even if the dogs didn't improve their lifespans (which honestly, I doubt they didn't) we are still in a similar ratio.