Transcript DESERT ADAPTATIONS PLANTS Plants have many adaptations to

DESERT ADAPTATIONS
PLANTS
Plants have many adaptations to
cope with the lack of water in the
desert.
•The barrel cactus has an
expandable stem for storing water.
•Some other plants have
adaptations that reduce water loss
from their leaves (this is where most water
is lost)
–Some have a waxy coating on
their leaves
–Some have small leaves or no
leaves at all
•
•
Annual Plants:
annual plants on the desert survive periods
where water is in short supply because their seeds
germinate only after heavy rain, grow rapidly, and live their
whole life-cycle in just a few days.
Perennial Plants: they endure the dry periods and make the
most of the scarce water supplies.
– Grasses have large and complex root systems that allow them to
collect water over a wide area.
– Bunchgrasses grow in isolated tufts. This reduces competition
between plants and assures each tuft of grass its own territory
from which to draw water. They also grow tightly together which
also conserves water that would be evaporated by the wind.
ANIMALS
Almost all animals in the desert stay out of the sun during the
hottest part of the day. They stay deep underground in burrows
where it is much cooler.
Most animals get their water from the food they eat. Green
leaves contain a lot of water. Carnivores get water from the
bodies of their prey, which contain liquid in the blood and tissues.
• Conserving water is important for desert mammals. Some small mammals:
– Have no sweat glands
– Pass no urine or very concentrated urine like the kangaroo rat.
– Acquire all or most of the moisture they need from the food they eat.
• Bats, most rodents and some larger
mammals, like coyotes and skunks,
are nocturnal…active at night when
it is cooler and sleeping during the
hot daylight hours.
• Several animals have evolved long
appendages to dissipate body heat into
their environment.
– The enormous ears of the jackrabbit and
mule deer release body heat when the
animal is resting in a cool, shady location.
TROPICAL
RAINFOREST
ADAPTATIONS
Plants in the rainforest have adaptations that
enable them to shed water efficiently.
The leaves of many rainforest plants have drip tips for this
purpose.
Tropical rainforest plants also have adaptations to take in
what little sunlight is available on the dark forest floor.
PLANTS
• Large leaves are common; they increase the
amount of sunlight a plant can capture.
• Other plants, like orchids, bromeliads and ferns,
grow as epiphytes (a plant that grows on another plant upon
which it depends for mechanical support but not for nutrients) high up
in the canopy where there is more sunlight.
• Because the weather is hot and wet, trees do not
need thick bark to slow down moisture loss and have
instead thin, smooth bark.
• They layers of rainforest are connected by vines and
ferns, and mosses grow on the trees. Liana is a
climbing vine that grows on rainforest trees, climbing
into the canopy so its leaves get more sunlight.
• Some trees have above-ground roots called prop or
stilt roots which give extra support to the trees.
These roots can grow about 85 cm in a month.
ANIMALS
• Because there are so many animals competing for food,
many animals have adapted by learning to eat a
particular food eaten by no other animal.
• Toucans have adapted by developing a long, large bill.
This adaptation allows this bird to reach fruit on
branches that are too small to support the bird’s weight.
The bill is also used to cut the fruit from the tree.
• Many rainforest animals use camouflage to ‘disappear’ in
the rainforest. Stick insects are perfect examples of this.
• There are also some butterflies whose wings look like
leaves.
• Camouflage is of course useful for predators too, so that
they can catch prey that hasn’t seen them. The boa
constrictor is an example of a camouflaged predator.
• Monkeys and apes have adapted cleverly to tropical
rainforests. All have long arms to use the canopy to swing
through the trees, avoiding ground predators.
• An aye-aye’s large eyes allow more light in at night, and
it uses echolocation to find its prey in the dark.
TEMPERATE DECIDUOUS FOREST
ADAPTATIONS
PLANTS
• In the spring, deciduous trees begin producing thin, broad,
light-weight leaves. This type of leaf structure easily
captures the sunlight needed for food production
(photosynthesis).
• The broad leaves are great when temperatures are warm
and there is plenty of sunlight. However, when
temperatures are cold, the broad leaves expose too much
surface area to water loss and tissue damage. To help
prevent this damage from occurring, deciduous trees make
internal and physical adaptation that are triggered by
changes in the climate.
• Cooler temperatures and limited sunlight are two
climatic conditions that tell the tree to begin adapting. In
the fall, when these conditions occur, the tree cuts off the
supply of water to the leaves and seals off the area
between the leaf stem and the tree trunk.
• With limited sunlight and water, the leaf is unable to
continue producing chlorophyll, the “green” stuff in the
leaves, and as the chlorophyll decreases the leaves
change color.
ANIMALS
• Migration and hibernation are two adaptations used by
the animals in this biome.
• While a wide variety of birds migrate, many of the
mammals hibernate during the cold winter months when
food is in short supply.
• Another behavioral adaptation some animals have
adopted is food storage.
• The nuts and seeds that are plentiful during the summer
are gathered by squirrels, chipmunks, and some jays, and
are stored in the hollows of trees for use during the
winter months.
• Cold temperatures help prevent the decomposition of the
nuts and seeds.
TUNDRA ADAPTATIONS
PLANTS
• Growing close together and low to the ground are
some of the adaptations that plants use to survive.
• This growing pattern helps the plant resist the effects
of cold temperatures and reduce the damage caused
by the impact of tiny ice particles of ice and snow
that are driven by the dry winds.
• Plants also have adapted to the arctic tundra by
developing the ability to grow under a layer of snow, to
carry out photosynthesis in extremely cold temperatures,
and for flowering plants, to produce flowers quickly once
summer begins.
• A small leaf structure is another physical adaptation that
helps plants survive. Plants lose water through their leaf
surface.
• By producing small leaves the plant is more able to retain
the moisture it has stored.
ANIMALS
• Migration and hibernation are examples of behavioral
adaptations used by animals in the artic tundra.
• The fact that many animals do not live year-round in the
tundra means they leave or migrate for a length of time
to warmer climates.
• Hibernation is a combination of behavioral and physical
adaptations.
• For example, during the summer the brown bear’s
physical adaptation allows the food eaten during the
summer to be stored as a layer of fat underneath its skin.
• The layer of fat insulates the bear from the cold. While in
hibernation the fat is slowly converted into energy that
maintains life.
OCEAN ADAPTATIONS
• Most ocean plants have adapted by developing gas
or air sacs lift them towards the surface of the water,
to collect sunlight.
• Examples of this type of adaptation include Sargasso sea
weed, which are sometimes called ‘sea grapes’ because of
the visibility of the gas sacs.
PLANTS
• On oceanic plants, the root structure is called a keepfast,
and is an adaptation to anchor the plants against the
currents and causing no need for internal water
transportation within the plant.
• Most oceanic plants are classified primarily as macroscopic
algae than vascular plants
• Ocean plants have to be able to handle the dissolved salt
in the water; the adaptation breaks down salt slowly and
stores it and passes it along with the respiratory products
of the plants.
• This can cause beds of oceanic plants to directly regulate
the salinity of the water in their region for their own
optimum environmental niche!
ANIMALS
• Fish can drink salt water, and eliminate the salt
through their gills.
• Seabirds also drink salt water, and the excess salt is
eliminated via the nasal, or “salt glands” into the
nasal cavity, and then is shaken or sneezed out.
• Whales don’t drink salt water - instead get the water
they need from the organisms they eat.
• Fish and other organisms that live underwater can take
their oxygen from the water, either through their gills or
their skin.
• Marine mammals need to come to the water surface to
breathe, which is why the deep-diving whales have
blowholes on top of their heads, so they can surface to
breathe while keeping most of their body underwater.
• In the oceans, water pressure increases 15 pounds per square
inch for every 33 feet of water. While some ocean animals do
not change water depths very often, far-ranging animals such
as whales, sea turtles and seals sometimes travel from
shallow waters to great depths several times in a single day.
– To accommodate this pressure change some species have
collapsible lungs and/or rib cages
• Animals in the intertidal zone do not have to deal with
high water pressure, but need to withstand the high
pressure of wind and waves.
• Many marine invertebrates and plants in this habitat
have the ability to cling on to rocks or other substances
so they are not washed way, and have hard shells for
protection.
• Species in this region also need to be highly adaptable to
both dry and wet environmental changes throughout
daily tides!!
• Organisms that need light, such as tropical coral reefs
and their associated algae, are found in shallow, clear
waters that can be easily penetrated by sunlight.
• Since underwater visibility and light levels can change,
whales do not rely on sight to find their food. Instead,
they locate prey using echolocation and their hearing.
• In the depths of the ocean abyss, some fish have lost their
eyes or pigmentation because they are just not necessary.
• Other organisms are bioluminescent, using lightproducing bacteria or their own light-producing organs to
attract prey or mates.