Hi! I'm Peter and I have green eyes, just like my mom.
A trait is a feature of an organism.
The DNA chromosomes of the polar bear and grizzy bear are vey different. For example the polar bear is white and the grizzly bear is brown or coloured. They need different climates to survive. Overall they have lots of genetic variation, because of their different genes and chromosomes.
The polar bears were separated for a long time and could reproduce offspring. They reproduced offspring with another species, and created a new species.
The grizzly bear travelled very far, and kept travelling and ended up in Antarctica. They started dying beacuse their fur was not thick enough to keep them warm, and they were spotted easily by predators.
The grizzly bears slowly started to adapt and lose the pigmentation of their fur and started to become white wuth thicker fur, whuch ultimately made what we know as POLAR BEARS!
All of the snow melted. The polar bears had lost their polar amd could not live. They did not reproduce. They all died. Polar Bears had gone EXTINCT!