Characteristics of Class Aves
Characteristics:
- i) Members of these groups are called birds.
- ii) The organisms in this group are very beautiful and have melodious voices.
iii) There are more than 9000 species are present of birds.
- iv) They are found in forests, deserts, and on mountains.
- v) Some birds live in the dark caves.
- vi) The forelimbs are in the shape of wings.
vii) Hind limbs held in walking
viii) All the birds have horny beaks.
- ix) All the birds lay eggs.
- x) All the birds must have two wings.
- xi) Their digestive system is able to digest thigh caloric food.
xii) They have high blood pressure and high metabolic rate.
xiii) Eyesight is well developed.
xiv) Nervous system is also well developed.
Groups of birds:
Birds are divided into two groups.
Running Birds: – (Ratitae)
Running birds have flattened sternums and their pectoral muscles are less strong e.g. Ostrich, Emu, Rhea, Cassowary etc. Ostrich is the Iarges bird. It can run 42-70 km/h.
Flying Birds: – (Carinatae)
Pectoral muscles are very strong and powerful. This helps them to fly. Their common examples are pigeon, crow, kite etc. Humming bird is smallest in the world. Its size is two inches long.
Dignity Aesthetic appearance; High memorability of information; This is how the child develops an adequate idea of the world. So, in terms of intellectual and emotional development, paper books at an early age are irreplaceable. There is a perception that prolonged reading impairs vision. On the one hand, this is so: if a child reads books with small print for a long time and without good lighting, the eyes get tired and, with chances, vision weakens. But for this there must be a predisposition of the organism.