Warm blooded animals, living in colder climates, tend to have shorter limbs, ears and other appendages when compared to the members of the same species in warmer climates.

Stenohaline Animals	Euryhaline Animals
The animals which show tolerance only to a narrow range of salinities.	The animals which, can tolerate a wide range of salinities
Their distributional range is limited.	Their distribution shows a wide range

1. The characteristic of soil that determines the movement of water through pore spaces is known as soil permeability.
2. Soil permeability is directly dependent on the pore size. Water holding capacity of the soil is inversely dependent on soil porosity.

Soil formation is called pedogenesis soil is formed from rocks which are the parent materials of soil, by weathering and is called embryonic soil (So soil is an edaphic factor).

Ecological niche is a term for the position of a species within an ecosystem, describing both the range of conditions necessary for persistence of species, and is ecological role in the ecosystem.

The natural home (or) environment of an animal, plant or other organism or it can be considered as the address of an organism

(i) The proportion of the age groups in a population is its age distribution attribute.
(ii) This determines the reproductive status of the population at the given time and is an indicator of the future population size.
(iii) Usually a rapidly growing population will have larger proportion of young individuals.
(iv) A stable population will have an even distribution of various age classes.
(v) A declining population tends to have a larger proportion of older individuals

No.	Tundra Biome	Taiga Biomes
1.	This is almost treeless plain in the northern parts of Asia, Europe, and North America.	Taiga is a forest of coniferous trees such as spruce, fir and pine.
2.	Winters are long with little daylight, summers are short, with long daylight hours.	Summer temperature ranges from 10octo 21oPc.
3.	Because of the severe winters, many of the animals are migratory. For E g: the many shore birds and water fowl such as ducks and geese, nest in the Tundra during the summer and migrate south for the winter.	Important migratory herbivores include moose, elk, deer and reindeer. Moose and reindeer migrate to the Taiga for winter and to Tundra for summers.

(i) The inherent tendency of all animal populations is to increase in number. But it does not increase indefinitely.
(ii) Once the carrying capacity of the environment is reached, population numbers remain static or fluctuate depending on environmental conditions.
(iii) This is regulated by many factors which are:
1. Density independent - Extrinsic factors
2. Density dependent - Intrinsic factors
(iv) Extrinsic factors include the availability of space, shelter, weather, food, etc.
(v) Intrinsic factors include competition, predation, emigration, immigration, and diseases.

S. No. Natality Mortality 1. It refers to the number of births per unit
population per unit time. e.g., per thousand
individuals per year in humans. It refers to the number of deaths per unit population per unit time. e.g., per thousand individuals per year in humans. 2. It adds new members to the population It removes members from the population 3. It increases the size of population. It decreases the size of population 4 Natality adds to population density Mortality reduces density of population 5 It maintains continuity of population It maintains health of population 6 It is high when population size is small and low when population size is large. Mortality is low when population
size is small and high when population size is large

Characters of biome 
(i) Location, geographical position (Latitude, Longitude)
(ii) Climate and physiochemical environment
(iii) Predominant plant and animal life
(iv) Boundaries between biomes are not always sharply defined. Transition or transient zones are seen as in case of grassland and forest biomes.

Every living organism responds to its environment. There are various ways by which organisms respond to abiotic conditions. The types of response observed are:
Regulate:
1. Some organisms are able to maintain homeostasis by physiological means which ensures constant body temperature, ionic/ osmotic balance. Birds, mammals and a fewer lower vertebrate and invertebrate species are capable of such regulation.
Conform:
1. Most animals cannot maintain a constant internal environment.
2. Their body temperature changes with the ambient temperature.
3. In aquatic animals like fishes, the osmotic concentration of the body fluids changes with that of the ambient water osmotic concentration. Such animals are called conformers. In case of extreme condition, the inhabitants relocate themselves as in-migration
Migrate:
1. Organisms tend to move away temporarily from a stressful habitat to a new, hospitable area and return when the stressful period is over.
2. Birds migrate from Siberia to Vedanthangal in Tamilnadu to escape from the severe winter periods.
Suspend:
1. In certain conditions, if the organism is unable to migrate, it may avoid the stress by becoming inactive.
2. This is seen commonly in bears going into hibernation during winter.
3. Some snails and fish go into aestivation to avoid summer related problems like heat and desiccation.
4. Some lower animal suspend a certain phase of their life cycle which is to as diapause.