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Class Level and Curriculum Links
Senior Primary Students
SESE Science:
Strand: Living Things
Strand Unit: Plant and Animal Life
* Identify the inter-relationships and interdependence between
plants and animals found in a habitat.
* Observe and explore some ways in which plant and animal behaviour
is influenced by, or adapted to, environmental conditions.
Junior Certificate Science
Leaving Certificate Biology:
1.5.5 Organism Adaptations
Adaptations on the bog
Example 1: Predators
Because there are no trees on bogs, most bird species are ground
nesting. The disadvantage of this is that if a predator does
come along a bird may be very vulnerable - unless it can hide,
by having a plumage which blends with the background vegetation
so that it almost becomes invisible to the casual observer. The
Red Grouse is a bird of bogs that adapts in this way.
The eggs of the Skylark are mottled brown and are well camouflaged in the bog vegetation. This reduces the possibility of them being found by predators such as the Fox.
The body of the Viviparous Lizard is striped which helps to break up the outline of the animal on the bog. Again the colour of the lizard matches that of the bog vegetation. Both factors are adaptations to avoiding predators.
Example 2: Exposure
The exposed conditions on the bog mean that plants are susceptible
to water loss. The wet bog surface means that it is extremely
difficult for plants to grow without drowning, except on the
drier hummocks of moss. The contant wind and the drying out of
the moss hummocks in summer means that plants are in danger of
drying out altogether. To overcome this difficulty the plants
are specially adapted to withstanding drought.
The leaves of Ling Heather are very reduced in size, no more
than a few millimeters. They are protected by a waxy cuticle
and they overlap one another rather like the tiles on the roof
of a house. These features help the plant to conserve water.
The leaves of the heathers such as cross-leaved heath and bog
rosemary are inrolled on their undersides. In addition the pores
in the leaves of these plants which open to the underside are
protected by a layer of white hairs.
Example 3: Nutrient poorness of the
acid peat bog
A number of the bog plants overcome the nutrient poorness of
the bog by being carnivorous. These carnivorous plants employ
two methods of catching their prey. The Sundews and Butterworts
produce sticky substances that act like fly paper, while the
Bladderworts trap their prey.
There are three species of sundew found on Irish bogs. The leaves of these plants are spoon-shaped. the surface of the "spoon" is covered with tiny tentacles that are topped with a drop of sticky fluid. Insects are trapped among the tentacles, which bend and enclose them. The whole leaf folds over like a clenched fist as the insect is digested for its nutrients.
The leaves of Butterworts are bright yellow-green and sticky. Insects stuck on the surface are digested by chemicals produced by the plant.
The Bladderworts are found in bog pools and have submerged leaves bearing tiny bladders that are used to trap insects. To accomplish this a bladder is fitted with a trap door and a trigger hair. When the prey touches the trigger hair, the door opens, releasing the partial vacuum within and sucking in the animal with a drop of water. In an instant the door shuts on the victim, which is subsequently digested.
Example 4: Aquatic Life
Water spiders and other diving water beetles overcome the need
to obtain oxygen under the water while hunting by trapping an
air bubble at the surface of the pond beneath their abdomen,
and using this while under the water to breathe. Similarly the
water boatman traps a layer of air around its wing cases to help
it breathe beneath the water. Pond skaters and raft spiders are
adapted to moving on the surface of the water by having legs
that are well spread out enabling the animal to evenly distribute
its weight.
Example 5: Submergence
The stems of the bog bean are usually fully submerged in bog
pools. The structure of these stems appears honeycombed in cross
section. There are air spaces within the stems so that plant
roots can obtain oxygen. The whole stem has a spongy texture.
