How do species adapt to their surroundings?

Several fish species can change sex as needed. Other species adapt to their surroundings by living long lives — or by living shorter lives and having lots of offspring. The ability of animals and plants to change can sometimes manifest in apparently extreme ways.

An acidic ocean may mean less fish

Calanus finmarchicus makes up about 90 per cent of the bottom of the food chain in northern oceans, and is eaten by fish and baleen whales alike, but as the ocean becomes more acidic due to CO2 emissions, populations may decrease dramatically.