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What are Aves?

Aves

• Birds are a group of warm-blooded vertebrates constituting the class Aves which have a four-chambered heart as well.

Four-chambered heart

• Birds have a streamlined body which helps them in piercing through the wind
• Their body is completely covered in feathers and their forelimbs are modified to form wings that help them
• Birds are all oviparous and lay

• They have a well-developed respiratory system consisting of lungs for

What are Mammals?

Mammals

• Mammals are a group of vertebrate animals constituting the class Mammalia.
• This class consists of all higher and complex organisms that have the most developed forms of
• Mammals show the presence of specialized structures on their body called Mammary glands which help in milk production. The milk is useful in nourishing the young babies till the time they can be fed on food which adults

Four-chambered heart

• Mammals are warm-blooded animals and have a four-chambered heart which helps in keeping the oxygenated and deoxygenated blood
• The skin of mammals is mostly covered with hair or fur for protection. Apart from this, there are specialized glands, sweat gland and oil gland, on the surface of the skin which help in secretion of sweat and useful oils that keep the skin moist and
• Mammals are viviparous except platypus and All mammals except these two-give birth to young ones directly.