I believe the answer is The second one, They have greater access to food in northern regions during the summer.
Hope this helped :)
Increased gill surface area has allowed the cichlids to better absorb the limited oxygen in the water.
I hope it help and if it did :))))))
Animals depend on food and without food it will break our animal food source chain. for example cows depend on hay and lions depend on meat from cows or something like that
A. true, because aflatoxins are harder to identify than other food-borne illness, and by the time it is in you, you are already sick.