Starch is a polymer of billions of glucose units joined through a condensation reaction that splits out molecule of water. Starch is an important part of our food belonging to the category of carbohydrates. It is found in cereals and potatoes.
Starch can be in two forms based on the their structure and some other differences:
1) Amylose- straight chain polymer
2)Amylopectin- Branched chain polymer
You can see the structure of starch with glucose monomers for better understanding in the image.
The animals can't adapt to the change. This causes them suffer and die outside of their natural zone. It can cause them to go extinct if left this way.