winter has cold weather & some animals' fur grows thicker for staying warm in the winter ->  some animals grow thicker fur in cold weather  some animals shed fur in spring & spring has warm weather ->  some animals shed fur in warm weather  some animals grow thicker fur in cold weather & some animals shed fur in warm weather ->  some animals grow thicker fur in cold weather and shed fur in warm weather  spring has warm weather & spring is a kind of season ->  the spring season has warm weather  winter has cold weather & winter is a kind of season ->  the winter season has cold weather  the spring season has warm weather & the winter season has cold weather ->  the spring season has warm weather and the winter season has cold weather  the spring season has warm weather and the winter season has cold weather & seasons cause change to the environment ->  the seasons changing from spring to winter causes the weather to change from warm to cold  some animals grow thicker fur in cold weather and shed fur in warm weather & the seasons changing from spring to winter causes the weather to change from warm to cold -> some animals grow thicker fur and shed fur as a response to changes in seasons