How do species survive Drought?

Answer 1

This question could be answered in a book!

• To survive the drought the species must overcome the problem of lack of water.
• Some species of frogs burrow into mud, shed skin cells to form a waterproof bag around themselves. Thus they hibernate in small balls of hardened mud and can be reawakened by the next rain even if that is in five years. Imagine the surprise of Europeans to find rocks in Australia that turn into hopping croaking frogs in the rain.
• Some animals that are used to periods of long spells of dry weather do not urinate but rather deposit the uric acid as a solid. This conserves water.
• Some animals can delay development of the foetus or fertilised ovum until the season is good enough to ensure enough food supply for survival eg Kangaroos, freshwater "sidewalker" crabs from Northern Territory
• Some animals eg some crustaceans will lay eggs that can remain dormant until the rain comes.
• Some marsupials hide in cracks in rocks, surviving for long periods without rain.
• Crocodiles can survive for over a year without eating, will immerse themselves in mud that can harden and cocoon the animal.
• Seeds of plants that are drought resistant have hard waxy coating that allows the seeds to remain dormant for years until the rain comes. Lotus seeds can survive for over 200 years.
• Some plants produce spores or spore like seeds that lie dormant until it rains.

The term drought is a relative one. In some countries, rain is regular and plentiful, therefore, a month or 6 months without rain is a drought. For some countries 5 to 8 years without rain is normal. Drought is an introduced term in Australian indigenous languages. Eyre's Lake in central Australia teems with glorious wildlife and flowers every few years, otherwise, it is pretty much a salt pan.

Answer 2

There are a variety of plant adaptations which enable certain species to survive a drought. One of the most common adaptations is that which succulents (such as cactuses) use, whereby they store water in the fleshy pulp of the plant, whether it be in its leaves or its trunk. Other adaptations include: * Some plants have roots that go down deep to reach the water table. * Other plants have roots that spread wide to take advantage of surface water. * Some plants, such as the mulga in Australia, have tiny leaves which grow upwards to catch rain droplets. Their branches and trunks are shaped to capture and channel as much condensation as possible down to a central root system. * Spinifex, a grass of the desert, has roots which grow both away from the plant to get surface rainwater and also grow down to reach deeper groundwater. Their leaves curl inwards, making a hollow tube which helps stop water droplets from evaporating. * River red gums grow alongside waterways in Australia. They grow very slowly during drought, but even new seedlings have a single root that will grow straight down to the groundwater. When the river suddenly floods, and perhaps even stays flooded for a long time, the river red gum has floating bundles of roots which take oxygen out of the water so the trees do not drown.

Answer 3

plants survive by allowing their roots to go deep down to reach the water below

Answer 4

Some of them can hold water in them selves, but most amphibians live in biomes where they do not have to worry about that.