How do Living Organisms Cope with Environment?

(i) Regulaters:-

• Some organisms maintain homeostasis by physiological and behavioural means.
• All birds and mammals and few lower vertebrate and invertebrate species maintain homeostasis by thermoregulation and osmoregulation.
• The success of mammals is largely due to their ability to maintain a constant body temperature.
• In summers, when outside temperature is more than our body temperature, we sweat profusely and the resulting evaporative cooling brings down the body temperature.
• Whereas in winters, when temperature is lower we shiver, a kind of exercise that produces heat and raises the body temperature.

(ii) Conform

• Majority (99%) of animals and nearly all plants cannot maintain a constant internal environment.

(iii) Migration

• The temporary movement of organisms from the stressful habitat to a more hospitable area and return when favourable conditions reappear, is called migration.
• E.g.:- In winter, famous Keolado National Park (Bharatpur) in Rajasthan hosts thousands of migratory birds coming from Siberia and other extremely cold northern regions.

(iv) Suspend

• Some bacteria, fungi and lower plants, under unfavourable conditions slow down metabolic rate and form a thick – walled spore to overcome stressful conditions.
• These spores germinate under coming of suitable environment.
• The animals that fail to migrate might avoid the stress by escaping in time, e.g., bear goes into hibernation during winter.
• Snail and fish go into aestivation to avoid summer.
• Zooplanktons under unfavourable conditions enter diapauses, a stage of suspended development.