sentence: Most birds stay together for the whole nesting season, and one advantage is that the work is shared.
sentences_before: Once the 'hen' has mated, she produces fertile eggs which have chicks growing inside them. She lays the eggs in the nest. There might be just one egg or a number of them, called a 'clutch'. Emus might lay as many as fifteen huge dark green eggs in a clutch. After the eggs are laid, they are 'incubated', or kept warm so the chicks form inside.
sentences_after: Many birds take turns sitting on the eggs, so that each adult can feed.
concept_name: bird
headings: Bird Behaviour Hatching
categories: Basic English 850 words