Living things & the processes of life - Interaction of living things with their environment - Our environment - G21 |
Teacher's Guide
LT-D3.2 |
Butterflies at Strathyre Primary School (access to video - probably only suitable if you have Broadband or a great deal of patience!)
see more on this Project |
2. This is a big subject area and there are plenty of excellent books which can guide you through the plants and animals to be found in each habitat.
The adaptations in animals and plants are concerned with things like :- a) Surviving lack of water (drought) - Snails can seal themselves away in their shells with a ‘front door’ made from dried mucous. They keep moist inside their sealed shells until it rains again and the dries mucous seal dissolves and they come out again. Plants adapt to drought by having thick waterproof surfaces to their leaves which cut down water loss. b) Surviving flooding - Frogs and toads are adapted to a life in damp or wet conditions. They have webbed feet for swimming, lay their eggs in water and can survive underwater for short periods. Some plants prefer a waterlogged habitat and have root systems which can withstand being continuously in water. c) Surviving exposure - Exposed hillsides where there is little shelter are home to sheep - wool protects them from the elements, birds who are able to shelter right down in the grasses and a variety of insects - even midges which are able to survive extreme conditions and starvation waiting for their next meal! d) Shortage of food - Hedgehogs, frogs, toads, grass-snakes and many insects are able to hibernate through the winter when they would otherwise face a severe shortage of food. They are able to lower their metabolic rate and body temperature to a sort of ‘tick-over ‘ level and sleep through the cold months. Squirrels don’t hibernate but go into a sleepy state which they emerge from periodically to go and fetch another nut from their store. e) Surviving exposure to salt and wind - in the case of marine environments this would be enough to kill most plants. The plants which can survive are things like tough grasses and small creeping plants which are somehow able to overcome the drying effect and the salt. Animals such as rabbits live quite close to the shore but are able to burrow in the soft soil and so escape the worst of the weather. f) Surviving immersion in sea water - regularly through the tides or occasionally through storms. Animals which survive in the tidal zone of the beach have to be able to withstand high temperatures and drying out in summer, cold and submersion in salt water twice a day. They tend to be things like anemones which can move around until they find a spot on a rock which is out of the direct sunshine and will move into a rock pool if possible. They are able to pull in their tentacles and close their mouth aperture to conserve moisture and prevent drying out. Many other animals have tough shells or skin to prevent them being damaged by waves and stop them drying out in between tides e.g. crabs which also bury themselves in the sand to prevent drying out. Some seaweed is specially adapted to survive in this zone. It tends to have thick leathery surfaces to prevent loss of moisture and be brown in colour so that it can photosynthesise underwater - it uses fucoxanthin instead of chlorophyll. g) Surviving attack from marauding animals such as birds and foxes. Hedgehogs are well adapted with their spines and ability to curl up, making them unappetising to most predators. See Hedgehog cull in the Western isles (BBC website). Many small birds will gang together to attack larger birds of prey. Mice and voles are well camouflaged and difficult to spot especially when they are still. |