THE HIMALAYA REGION

ALTITUDE INFLUENCES THE FLORA AND THE FAUNA IN THIS REGION. THE CLIMATIC CONDITIONS SIMILAR TO THE ARCTIC REGIONS  ARE FOUND AT HIGHER ELEVATIONS OF THE HIMALAYAS.APART FROM THE ECOLOGICAL CHANGES DUE TO ALTITUDE IN THE HIMALAYAS, THERE IS A MARKED EAST-WEST VARIATION DUE TO THE WEST- WARD DECREASE IN THE MONSOON RAINFALL. THE WESTERN HIMALAYAS HAVE LOW BUT HEAVIER SNOWFALL AS COMPARED TO THE EASTERN HIMALAYAS WHILE RECEIVE MUCH MORE RAINFALL AND SNOWFALL ONLY IN THE VERY HIGH ALTITUDES. THE CLIMATIC CONDITIONS OF THE LOWER ALTITUDES OF THE EASTERN HIMALAYAS RESEMBLE THAT OF THE TROPICAL RAIN FOREST. THE TEMPERATE REGION IN THE EASTERN REGION STARTS  ABOVE 2745 METERS AS AGAINST 1500 METERS IN THE WESTERN HIMALAYAS.

ECOLOGICAL SUB-DIVISIONS

THE PRESENT PHYSICAL FEATURES AND CLIMATE OF INDIA TOGETHER WITH THE IMMENSE FAUNA CHANGES THAT TOOK PLACE DURING THE LATE PLIOCENE PERIOD HAVE IMPARTED TO ITS FLORA AND FAUNA, A WIDE VARIETY OF HABITATS, EACH SUPPORTING ITS DISTINCTIVE TYPE OF FLORA AND FAUNA.

INDIA AS A MEGA DIVERSITY NATION

THE GREAT VARIETY OF ECOLOGICAL CONDITIONS PREVAILING IN INDIA ALLOWS IT TO SUPPORT AN ENORMOUS DIVERSITY OF WILD LIFE, INCLUDING, HOT DESERT FORMS, LIKE THE WILD ASS AND THE COLD DESERT FORMS, LIKE THE TIBETAN ANTELOPE; ANIMALS OF OPEN SCRUBLAND, LIKE THE RHINOCEROS; ANIMALS OF THE DECIDUOUS FORESTS LIKE THE WILD GAUR AND OF THE TROPICAL RAIN FORESTS, LIKE THE LION-TAILED MACAQUE.


THE UNIQUE BIO-GEOGRAPHIC POSITION OF THE INDIAN SUBCONTINENT IS RESPONSIBLE FOR THE GREATER DIVERSITY IN INDIA'S WILDLIFE. INDIA LIES AT THE CONFLUENCE OF ETHIOPIAN, PALAEARCTIC AND INDO- MALAYAN FAUNAS AND POSSESS A NUMBER OF INTERESTING COMPONENTS FROM EACH OF THESE REALMS AS WELL AS SEVERAL INDIGENOUS VARIETIES. THE ETHIOPIAN ELEMENT IS REPRESENTED BY THE CHINKARA, THE HYENA AND THE RATEL; THE PALAEARCTIC BY THE LYNX, WOLF, HANGUL; THE CHINESE, BY RED PANDA AND MUSK DEER AND THE INDO-MALAYAN BY THE HOOLOCK GIBBON, THE ELEPHANT, THE GOAT ANTELOPE AND THE MOUSE DEER. THE ENDEMIC VARIETIES INCLUDE MELURSUS(SLOTH BEAR), ANTELOPE (BLACK BUCK), TETRACERUS (FOUR-HORNED ANTELOPE) AND BOSELAPHUS (NILGAI).


THE PRESENCE OR ABSENCE OF AN ANIMAL OR PLANT IN A CERTAIN REGION IS DETERMINED  BY ECOLOGICAL AND HISTORICAL FACTORS. POPULATIONS OF ORGANISMS CAN BE ESTABLISHED IN A REGION ONLY IT THE RANGE OF CONDITIONS PREVAILING THERE. ANIMALS AND PLANTS THEN ARE LIVING INDICATORS OF THE CHARACTERISTICS OF THEIR ENVIRONMENT. THEIR RANGES MARK THE PLACES IN WHICH ENVIRONMENTAL CONDITIONS ARE SIMILAR. AT THE SAME TIME, THE EVOLUTION  AND DISTRIBUTION OF SPECIES CASTS LIGHT UPON THE GEOLOGICAL EVOLUTION OF VARIOUS PARTS OF THE EARTH, AND UPON THE COURSE OF GLOBAL CHANGES IN CLIMATE AND VEGETATION.

ALLELOCHEMISTRY

THESE RELATIONSHIPS INVOLVE COACTIONS  WHEREBY CHEMICALS SECRETED BY ONE ORGANISM AFFECT THE GROWTH, HEALTH AND BEHAVIOUR OF OTHER ORGANISMS. ALLELOPATHY IS PRODUCED IN  PLANTS  WHEN TOXINS ARE LIBERATED THAT INHIBIT SEEDLING GROWTH IN THE VICINITY. THIS MAY AFFECT SUCCESSION IN PLANT SPECIES  ESPECIALLY IMPORTANT IN THE EARLY STAGES.ANTIBIOTICS PRODUCED BY BACTERIA, FUNGI AND LICHENS  ARE WIDESPREAD IN NATURE. ALLECHEMIC EFFECTS ARE  OF GREAT VARIETY IN BOTH PLANTS AND ANIMALS: REPELLANTS, ESCAPE SUBSTANCES, SUPPRESSANTS, VENOMS, INDUCTANTS, ATTRACTANTS, SIGNALS, STIMULANTS, AUTOTOXINS, ANTOINHIBITORS, ETC. PHEROMONES, CHEMICAL MESSAGES BETWEEN  MEMBERS OF A SPECIES ARE ESPECIALLY IMPORTANT IN REPRODUCTIVE BEHAVIOUR, SOCIAL  REGULATION AND RECOGNITION, ALARM AND DEFENCE, TERRITORY AND TRAIL MARKING, FOOD  LOCATION AND SO ON.

AGGREGATIONS

THE REACTIONS MADE BY LARGE POPULATIONS ON THEIR HABITAT SHOW CONSPICUOUS EFFECTS. DUE TO THE OCCURENCE OF WATER CONDITIONING, PHYSICAL AND CHEMICAL CHANGES OCCUR AS A RESULT OF ORGANISMS LIVING IN IT. COMPARED TO UNCONDITIONED WATER, THESE CHANGES MAY EITHER PROVE TO BE HARMFUL OR BENEFICIAL ON THE ORGANISMS INTRODUCED INTO THE WATER AFTER THE ORIGINAL ORGANISMS HAVE BEEN REMOVED. THE MARINE FLATWORM WILL SURVIVE MUCH LONGER, WHEN TRANSFERRED TO FRESH WATER CONDITIONED EITHER BY THE PRESENCE OF LIVING OR DEAD  INDIVIDUALS  OF THE SAME SPECIES OR BY THE PRESENCE OF FRESH WATER SPECIES OF FLATWORMS, THAN THEY DO IN UNCONDITIONED WATER. AGGREGATIONS ENSURE  LONGER SURVIVAL  OF ORGANISMS IN TOXIC  SOLUTIONS  THROUGH FASTER GROWTH AND GREATER REPRODUCTION.

BENEFITS DERIVED FROM AGGREGATIONS IN TERRESTRIAL ANIMALS ARE ALSO WELL DEPICTED IN HONEYBEES WHEN THEY FORM CLUSTERS AND MAINTAIN  A MASS TEMPERATURE SEVERAL DEGREES ABOVE OUTSIDE TEMPERATURES. WHEN THERE IS DANGER OF OVERHEATING, THE BEES IN THE HIVE SPREAD OUT ON THE COMBS AND FAN WITH THEIR WINGS TO CREATE A CIRCULATION OF AIR.

COMPETITION

THE WORD COMPETITION DENOTES STRIVING FOR THE SAME THING. AT THE ECOLOGICAL  LEVEL IT HOLDS GREAT RELEVANCE WHEN THE THING WHICH TWO ORGANISMS ARE STRIVING FOR IS NOT EASILY AVAILABLE. EVEN IF AVAILABLE, IT IS ONLY IN SMALL NUMBERS. IF POPULATION CONSISTS OF ONLY A FEW SCATTERED INDIVIDUALS COMPETITION WILL NOT BE A FACTOR OF ECOLOGICAL IMPORTANCE.

THE RESULT OF COMPETITION IS THAT BOTH PARTIES  COMPETING WILL BE HAMPERED IN SOME MANNER OR THE OTHER. AT THE POPULATION LEVEL, OR THE DESTINY OR RATE OF POPULATION, ENERGY  FLOW WILL BE REDUCED OR HELD IN CHECK BY THE COMPETITIVE ACTION. COMPETITION ALSO OCCURS WHEN TWO ORGANISMS STRIVE FOR SOMETHING THAT IS NOT IN SHORT  SUPPLY, YET THEY INTERFERE WITH EACH OTHER, OR THEY MIGHT EVEN EAT EACH OTHER. MANY ECOLOGISTS PREFER NOT TO  INCLUDE  THIS ASPECT UNDER COMPETITION.

PLANT POPULATION AS WELL AS ANIMAL POPULATION MAY REGULATE THEMSELVES TO AVOID OVER-CROWDING. DESERT SHRUBS ARE WIDELY SPACED, ALMOST UNIFORMLY DISTRIBUTED; THIS PATTERN EXPLAINS THE COMPETITION OF SCARCITY OF WATER.HOWEVER, EVOLUTION OF SELF REGULATION OF POPULATION HAS OCCURRED IN SOME SPECIES IN THAT SEVERE COMPETITION FOR WATER IS AVOIDED BY THE PRODUCTION OF LEAF OR ROOT HORMONES THAT INHIBIT DEVELOPMENT OF OTHER INDIVIDUALS IN THE NEIGHBOURHOOD.