HABITATS

Animals are found almost everywhere on the earth .They are found in fathomless depth  of the ocean ,at the highest peak of the mountains ,freezing cold of the polar region  or in scorthing heat of the deserts.Each of these regions may have  its own peculiar  fauna [stock of animals] The  animal may inhabit  the salt water of the sea  or the fresh water of the rivers and ponds They may live on  or in the soil ; some  may take  to air  and some  to the trees .Many  animasl reside on or  in the body  of other animals  as parasites .                                                       Marine habitats . About  three- fourth of the eath surface  is covered by the water of the oceans .The salt  water   of  seas  and oceans  serve as home  of the marine animals .These  may  live  either  on the sea-beach  or in the deep depth  of the sea  or on its bottom .They may be found in  the open sea .Those  marine animals  which live   on the sea beach  either in the sand  or  remain attached  to submerged  rocks are called littoral animals .Those  who lived at great depth  are called deep sea or abyssal animals , whereas those  living  on the bottom are called  benthonic animals  .The animals  found on the  surface of water  are pelagic   animals; they swim freely  [nektons]  or float [planktons] .                                    Fresh water  habitats. Animals  which occupy fresh water bodies  such as  rivers, lakes  ,ponds, and swamps are called fresh water animals .Such animals  may mostly occupy either  running or  stagnant water  The animals  living in the stagnant water [ponds, lakes,etc.] are called  lentic  forms ,whereas those  living in the running water [streams ,rivers] etc.] are called  lotic forms .The surround8ings  is hypoyonic to their body .Therefore ,  they  have water- regulatory mechanism in their body . Terrestrial habitats. Animals living  on the land are called  terrestrial animals . They  may live  on the surface or beneath the surface.Those  animals  which  live beneath the surface  if the soil are called  subterranean   or sub terrestrial  animals  .The  surface dwellers  may be  found on plains  , on rocks , no deserts  or in the damp forests .Their locomotory structure  fit well for the movement of the land .                                                                                         Besides ,some  animals have selected  air or trees as their habitats .Those animals which  inhabit  air are called   aerial animals.They spend most of their time  in the air and come to land  for the rest .Birds  and insects  are example  of aerial animals.The  animals  living  onthe trees   are called  arboreal animals .They spend  most of their time on the trees  but do  come to land  for feeding or other activity  for avery short period of the day and night .The squirrel  is an arboreal animal .