• Adaptations are structural and functional characteristics which organisms have developed during the course of evolution enabling them to survive and reproduce in a particular environment. The term adaptation has therefore an evolutionary significance.

Ecological Adaptation in Halophytes

• Halophytes are plants of saline environments, which are adapted to high concentration of salt in soil or water. Tidal marshes and coastal dunes, mangroves and saline soils support halophytes. In wet and marshy conditions of tropical deltas and along ocean edges mangroves are found. Few species of mangroves can excrete salt through salt glands on the leaf. Some plants can exclude salts from the roots through pumping excess salt back to the soil for coping with condition of high salt conditions and osmotic potential many mangroves have high level of organic solutes such as proline, glycine betaine, amino acid mannitol and sorbitol. Mangroves have developed adaptations e.g., pneumatophores, prop and stilt roots and vivipary (seed germinate while on the tree) to cope with high concentration of salt.

Ecological Adaptation in Animals

• Carnivorous and herbivorous animals have adaptations to eat a certain kind of food. Some animals have adaptations to avoid being eaten by the predators; others have behavioral adaptations to attract a mate. The males of some animals (particularly the plumage of the birds) have bright coloration, which gives advantage in sexual selection and mate attraction. However, a majority of animal adaptations to environmental variations and stress conditions are physiological and behavioral. Camouflage in some animals is a common example of adaptation. Some insects, reptiles and mammals have markings on their bodies which make it difficult to distinguish them from shadows and branches or from other members of the group. In very cold or dry environments, animals are not able to function normally. Under such conditions, the species that are not capable of migration, shift to a physiological dormant state. Hibernation is spending winter in dormant condition, whereas aestivation is spending the dry-hot period in an inactive state.

Ecosystem Services

• Healthy ecosystems are the base for a wide range of economic, environmental and aesthetic goods and services. The products of ecosystem processes are named as ecosystem services, for example, healthy forest ecosystems purify air and water, mitigate droughts and floods, cycle nutrients, generate fertile soils, provide wildlife habitat, maintain biodiversity, pollinate crops, provide storage site for carbon and also provide aesthetic, cultural and spiritual values. Though value of such services of biodiversity is difficult to determine, it seems reasonable to think that biodiversity should carry a hefty price tag.