/sci/ - Science & Math

Okay, I initially was going to ask this in /new/ -because they're the ones always talking about it- but I want a serious answer, so I decided to ask here instead. Please forgive my ignorance.

Essentially, they're always saying that all the wealthy, developed countries are wiping themselves out of existence with low birth rates. That once the population starts shrinking, the race is doomed. That Japan, Australia, and all of Europe will eventually no longer have their native population because Hispanics and Muslims are outbreeding them. That in 50-100 years time, whites will simply cease to exist or some shit.

So, if this is true... Why do we even bother with endangered species? Aren't they doomed to cease existing due to their limited gene pool, and shrinking population?

Just, someone explain this shit to me. Please.