The upcoming discussion will update you about the difference between orninthorhyncus and tachyglossus.
Difference # Orninthorhyncus:
Habit and habitat:
(a) Lives in burrows on river banks.
(b) Good swimmers. Swimming is done by paddling of limbs and body undulations.
(c) Lives on molluscs and worms.
(d) Cannot roll up into a ball for protection.
(e) Pinna is small and remains under cover of hairs
External morphology:
(a) Body is covered over with brown under fur and harsher outer fur.
(b) A flat bill, like that of duck, is present. The bill is hairless with tactile organs in pits.
(c) Nictitating membrane is present.
(d) Tail is broad and flat.
(e) Digits are webbed.
Internal Structure:
(a) Teeth—present in early stage but teeth are replaced by horny pad in adults.
(b) Tongue is small.
(c) Eardrum is very small.
(d) Brain is relatively small.
(e) Skeletal framework is rather simple.
(f) Gynaecomastism is supposed to be present.
(g) Two eggs are laid at a time and are placed in burrow.
Difference # Tachyglossus:
Habit and habitat:
(a) Terrestrial and lives on land with soft soil.
(b) Adapted to terrestrial life.
(c) Lives on ants.
(d) Can roll up into a ball for protection.
(e) Pinna is large, tubular and lies just behind the eye.
External morphology:
(a) Body is covered over with strong pointed spines and coarse hairs. Spines are absent on the ventral surface.
(b) A long pointed and tactile rostrum is present.
(c) Nictitating membrane is absent.
(d) Tail is vestigial.
(e) Digits are not webbed.
Internal structural:
(a) Teeth—absent at all stages of life.
(b) Tongue is long and protrusible. Secretion of salivary glands is sticky.
(c) Eardrum is large.
(d) Brain is relatively large.
(e) Skeletal framework is complex.
(f) Gynaecomastism is definite.
(g) One egg is laid at a time and is placed in a pouch by the mother.