In this week's class (and readings), the question "Why do we age?" has been greatly explored. Throughout yesterday's class, we explored many different reasons, like socioeconomic status, and just inevitability. A lot of aging has to do with the breakdown of DNA and how that affects the rest of the body. An idea that as we stop reproducing (due to age), our likelihood of dying increases, because natural selection does not really care about life after successful reproduction. So why do we age?
During some online research about this topic, I was able to find a nice article on National Geographic's website, which compares the aging and fertility between different species of organisms. I thought it was very interesting and informative. Something very interesting is that not all species experience a drop in fertility and a rise in mortality with age.
The desert tortoise, actually, experiences the opposite. As it ages, its fertility increases and its mortality decreases. This is not something we see in humans, or often in other animal species, which is particularly interesting. In a similarly interesting note, the Hydra (hydra magnipapillata), a water polyp, has nearly identical birth and death rates, all throughout its lifespan. This article also compares a few other species, but you'll just have to read it to find out!