Spoiler: evolution
I, personally, think it's pretty selfish for us humans to whine about the difficulty of low flow toilets while species go extinct, but if it helps justify action then do realize that life is going to suck for everyone - steaks and salmon both have very real limits on their survival as climate change continues.
Millions of years from now, sure. In the near term future: mass extinction. A mass extinction in the seas means that the 1 billion people that rely on the ocean as their primary protein source would be in deep trouble.