I think its that I'm not sure
The water would freeze across the surface of the lake, blocking the dissolving of oxygen and nutrients. <span>Water is actually less dense when frozen, which is why ice cubes and ice bergs all float. This is also why you can ice skate on a lake if the ice gets thick enough on the surface. Many organisms that live in freezing lakes have special adaptations which help them survive.</span>
Pituitary gland ( insufficient production of STH )
<span>Many mutations do produce changes in phenotype,I</span>t helps the bodies of the species to re-adapt to more locations and habitats.
