Adaptations
Why do animals and plants live in the places they do? Look at these two types of fish:
From observations of the features and the behaviour of each fish, inferences can be made about how they survive in their environment.
Adaptations are characteristics which ensure that an animal or plant survives in its habitat. Structural adaptations are characteristics of the organisms body for example, size of teeth, shape and size of body. Anemones have long waving tentacles to catch food. Behavioural adaptations have to do with the way an organism behaves. For example, crabs can burrow under sand during the day. Some fish have specialised systems that control water balance and allow the fish to compensate for changing salinities. This is an example of a physiological (or functional) adaptation.
Animals coping with their physical environment
There are a number of strategies of adaptation which enable organisms to survive in particular zones (eg. in the intertidal zone). These strategies fall into three main categories:
Fish have a number of adaptations. Refer to the table below and classify the adaptation as structural, behavioural or physiological. Conduct some research to discover which type of fish might have this adaptation. You will need to rule up and complete your own version of this table in your exercise book.
adaptations of rocky shore organisms
Form a group of 3-4 students and discuss the adaptive features of the following organisms. Be sure to determine which of the adaptations are structural, behavioural or physiological and state why they are so important. Film your group's discussion and share with your teacher via google drive.
Many animals, such as marine worms, do not have obvious structural features which would enable them to live in exposed areas of the shore, as do many snails. Frequently these animals have behavioural adaptations enabling survival in the intertidal zone.
These include;
- Living in a microhabitat (where the environmental stresses of the open shore are absent or reduced) eg. under a rock.
- Time of feeding - eg. extending, tentacles to feed only when the water in covering the animal, i.e.. during high tide
Can you think of any other adaptations that help marine organisms to survive in their environment? List 5-10 of these in your exercise book.
These include;
- Living in a microhabitat (where the environmental stresses of the open shore are absent or reduced) eg. under a rock.
- Time of feeding - eg. extending, tentacles to feed only when the water in covering the animal, i.e.. during high tide
Can you think of any other adaptations that help marine organisms to survive in their environment? List 5-10 of these in your exercise book.
Read the story about Sammy the Snail below. In your exercise book, explain the three behavioural adaptations Sammy and his family demonstrate.
What other adaptations do Sammy and his family exhibit? Are these structural or physiological?
Write your own creative short story including three adaptations for survival in the intertidal zone for Barney the Barnacle.
Write your own creative short story including three adaptations for survival in the intertidal zone for Barney the Barnacle.
adaptations of mangroves
Pneumatophores
One at the most striking features of all mangroves is the variety of ways in which their roots differ from normal land plants. Pneumatophores (breathing-roots) are part of an extensive root system that provides nutrition, water absorption, gases, support and anchorage in a soil which is oxygen-deficient, salty and often fluid. Of this extensive root system, only the pneumatophores are visible above the surface. Because of the lack of air in the muddy soil, they act as breathing roots. At low tide, they are exposed and able to soak up air which will be stored to carry the plant over the period of high tide. Pneumatophores, along with the spreading underground root system, may assist the build-up of sediments to form a level terrace in the mangrove zone.
One at the most striking features of all mangroves is the variety of ways in which their roots differ from normal land plants. Pneumatophores (breathing-roots) are part of an extensive root system that provides nutrition, water absorption, gases, support and anchorage in a soil which is oxygen-deficient, salty and often fluid. Of this extensive root system, only the pneumatophores are visible above the surface. Because of the lack of air in the muddy soil, they act as breathing roots. At low tide, they are exposed and able to soak up air which will be stored to carry the plant over the period of high tide. Pneumatophores, along with the spreading underground root system, may assist the build-up of sediments to form a level terrace in the mangrove zone.
Seeds and Seedlings
The germination of the seed while still attached to the plant is known as viviparity. Through viviparity, this White Mangrove has side-stepped the problem of germination in salt water. The germinated seedling falls to the ground in February and March, often drifting long distances on tides and currents before settling. Once deposited in a suitable muddy spot, the young plant quickly establishes roots, along with shoots and leaves.
The germination of the seed while still attached to the plant is known as viviparity. Through viviparity, this White Mangrove has side-stepped the problem of germination in salt water. The germinated seedling falls to the ground in February and March, often drifting long distances on tides and currents before settling. Once deposited in a suitable muddy spot, the young plant quickly establishes roots, along with shoots and leaves.
Salt and Leaves
Controlling the balance of internal salt and water is a problem for all coastal organisms, especially for such large land plants as the mangrove. There are three possible answers to the salt problem: prevent excessive salt absorption, develop tolerance of higher than normal internal salt concentration or develop a means of removing excess salt. The White Mangrove uses all three mechanisms. Firstly, the roots are designed to allow fresh water and essential nutrients in, while excluding most of the salt. Secondly, White Mangroves can tolerate up to one hundred times the internal salt concentration of normal land plants. Finally, they have special 'salt secreting' glands an the underside of their leaves. These glands actually pump salt out of the mangrove.
Controlling the balance of internal salt and water is a problem for all coastal organisms, especially for such large land plants as the mangrove. There are three possible answers to the salt problem: prevent excessive salt absorption, develop tolerance of higher than normal internal salt concentration or develop a means of removing excess salt. The White Mangrove uses all three mechanisms. Firstly, the roots are designed to allow fresh water and essential nutrients in, while excluding most of the salt. Secondly, White Mangroves can tolerate up to one hundred times the internal salt concentration of normal land plants. Finally, they have special 'salt secreting' glands an the underside of their leaves. These glands actually pump salt out of the mangrove.
Prop roots
As with pneumatophores, prop roots act as breathing roots. They are similar in structure to pneumatophores but, instead of growing up from an underground root system, they grow down from the trunk or lower branches of outer, seaward mangroves.
As with pneumatophores, prop roots act as breathing roots. They are similar in structure to pneumatophores but, instead of growing up from an underground root system, they grow down from the trunk or lower branches of outer, seaward mangroves.
Matching Exercise - Match the correct term to its definition in your exercise book.
Pneumatophores pump salt out of mangrove
Prop roots seed germination
Salt secreting gland help obtain oxygen
Viviparity provides nutrition, water absorption and support
Pneumatophores pump salt out of mangrove
Prop roots seed germination
Salt secreting gland help obtain oxygen
Viviparity provides nutrition, water absorption and support
assignment
Download a copy of the 'Adaptations Research Task' document from Edmodo and complete. You may have 30 minutes of class time to work on this, and the remainder is to be completed for homework.