Question

Both insects and mammals share an aquatic ancestor and both lineages over time evolved to live in a terrestrial environment.

a. What three shared characteristics of these groups (these must be multicellular ones)

b. What is an adaptation that is found in terrestrial insects that is not found in mammals?

Answer 1

Answer-a: The shared characterstics (or, similarities) of these groups are as follows-

1. Both possesses bilateral symmetry.

2. Both possesses HOX gene which plays crutial and vital role in their overall development.

3. A few exceptional mammals such as Duck-billed Platypus and Spiny anteater and all the insects lays eggs (oviparous)

Answer-b: Following adaptations are found in insects but not in mammals-

1. Insects have trachea for respiration, malpigian tubules for excretion and waxy cuticle to reduce water loss; whereas, mammals have lungs for breathing and kidneys (nephrons) for excretion.

2. Some terrestrial insects possess thin and long legs which enable them to run faster and to escape from their predators. For example- Americana periplanata (cockroach)

3. Some insects have strong and long hind limbs which helps them to jump higher. For example- Grasshoppers, which can jump over the grass to capture food for themselves due to this adaptation.

4. Certain insects, like, Cricket which lives under the ground have well adapted limbs which help them to dig the ground. Because of this adaptation, it becomes easy for them to eat grass' roots. Their front short legs act like a shovel and back strong legs act like digger.