Adaptations of animals to Habitat, Temperature and Light

Adaptations of animals to Habitat, Temperature and Light

Animals can adapt themselves according to their habitat. Temperature and light are forms of energy which influence various stages of life activities such as growth, metabolism, reproduction, movement, distribution and behaviour. Animals develop special features or behaviour patterns to escape from extreme conditions of temperature and light. In this context, let us study the adaptive features of bat and earthworm.

1. Adaptations of Bat

Bats are the only mammals that can fly. Mostly, bats live in caves. Caves provide them protection during the day from most predators and the temperature here is very stable. Apart from caves, bats also live in trees, hollowed logs and rock crevices. They are extremely important to humans as they reduce insect population and help to pollinate plants. Here, we will see the adaptations of bat in relation to their habitat.

Nocturnality

Bats are active at night. This is a useful adaptation for them, as flight requires a lot of energy during day. Their thin, black wing membrane (Patagium) may cause excessive heat absorption during the day. This may lead to dehydration.

Flight adaptation

Bat wings are entirely different from those of birds or insects. Modified forelimbs serve as wings. The bones in the wings of bats are elongated fingers and are connected by the flaps of skin on either side of the body known as Patagia. Tail supports and controls movements during flight. Muscles are well developed and highly powerful and achieve in beating of wings. Tendons of hind limbs provide a tight grasp when the animals are suspended upside down at rest.

Hibernation

Hibernation is a state of inactivity in which the body temperature drops with a lowered metabolic rate during winter. Bats are warm blooded animals but unlike other mammals, they let their internal temperature reduce when they are resting. They go to a state of decreased activity to conserve energy.

Echolocation

Bats are not blind. But to fly around and hunt for insects in the dark, they use a remarkable high-frequency system called echolocation. Bats give out high-frequency sounds (ultrasonic sounds). These sounds are reflected back from its prey and perceived by the ear. Bats use these echoes to locate and identify the prey.

2. Adaptations of Earthworm

An earthworm is a segmented worm which belongs to Phylum Annelida. It is commonly found living in soil, feeding on live and dead organic matter. The faecal wastes are called worm castings (Vermicasts) which are rich in nitrogenous content adding fertility to the soil. Earthworm plays a large role in keeping soil health facilitating aeration, water infiltration and producing organic matter to increase crop growth. Some of the adaptations of earthworm are explained below.

Stream-lined body

The earthworm has a cylindrical, elongated and segmented body. This helps them to live in narrow burrows underground and for easy penetration into the soil.

Skin

Mucus covers the skin which does not allow soil particles to stick to it. The slippery skin is kept moist as it respires through the skin. Moist skin helps in oxygenation of blood.

Burrowing

Its body is flexible having circular and longitudinal muscles which help in movement and subsoil burrowing. Each segment on the lower surface of the body has number of bristles called setae. They help the earthworm to move through the soil and provide anchor in the burrows.

Aestivation

When the soil becomes too hot or dry, earthworms become inactive and undergo a process called aestivation. Earthworm moves deeper into the soil. It secretes mucus and lowers their metabolic rate in order to reduce water loss. They remain dormant until conditions become favourable. They come out of their burrow during rainy season. The ideal temperature range is 60-80oF. The ability to tolerate temperature depends on the surrounding moisture in the environment.

Nocturnality

Earthworms are sensitive to light. It has no eyes but can sense light through light sensitive cells (Photo-receptors) present in their skin. They give the skin the capacity to detect light and changes in light intensity. They react negatively to bright light (Photophobic). It remains in its burrow during the day to avoid light.