Is every species necessary or can we let some die out?

The following is an extract from our nature newsletter Wild Wild Life. Sign up to receive it for free in your inbox every month.

There are many organisms teetering on the brink of extinction. Take the planet’s smallest marine mammals, vaquitas (Phocoena sinus), which are thought to now number fewer than 10 individuals in the Gulf of California, where they are constantly at risk from being caught in fishing nets. Or the last two remaining northern white rhinos (Ceratotherium simum…