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Blue Planet Challenge
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Animals of the deep sea have evolved as a result of adaptation to extreme conditions. Whilst we live in a much less extreme environment, we can still see evidence of similar adaptations in our own surroundings.
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What do we mean by adaptation?
Adaptation is the process by which a plant or animal changes to fit into its environment. It results from natural selection acting upon inherited variation or mutation. Adaptation may occur in any area, from internal structure to locomotion. To be most effective, several changes need to occur simultaneously. For example, if an animal changes its diet, it may also need to change its teeth, its digestive system and its predatory habits.
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Animal adaptation to urban life
Our towns and cities may seem extremely inhospitable to wildlife, yet towns can be surprisingly green areas and they offer diverse habitats. Even in rubbish dumps and derelict areas plants and animals do well. Some towns, such as Edinburgh, have a higher density of trees than their surrounding countryside.
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The following section gives you an idea of what to look out for:
Homes
For wildlife to survive in the home, it must often adapt to an environment with restricted daylight, drought and constant disturbance. Carpet beetles, clothes moths and meal moths can survive without water. Other species are simply nocturnal, only emerging when there is little or no disturbance.
Some animals, such as the house martin, have made a new niche for themselves, becoming almost completely dependent on urban life for survival. It is likely that the growth in housing has much to do with the population increase of this species.
Bats have exchanged woodland and cave roosts for lofts as habitat loss forces them into towns. Several seabirds have substituted sea cliffs for tower blocks. The herring gull that breeds in the city appears to do so more successfully than its relatives on the coastal cliffs. Kittiwakes that spend their entire winter far out to sea come inland to breed on the ledges of old warehouses in Newcastle-upon-Tyne.
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Gardens
There are over a million acres of garden in Britain, each containing 200-300 species of plants. As the plants move in, the plant-eating and tree-dwelling animals follow and after them come the predators. Foxes and even badgers have become regular visitors to city gardens.
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Abandoned areas
Rosebay, willowherb, daisies, ragwort and dandelions move in to colonise derelict areas. Nettles are a food plant for many attractive insects and soon invade areas that were once well fertilised. Gravel pits attract abundant species of bird especially migrant visitors wintering in Britain. Rubbish tips might be the end of the road for all our rubbish, but for gulls, invertebrates and foxes they are an abundant source of fast food.
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Pavements
This seemingly barren world is a patchwork of microhabitats. For organisms to survive, they need a range of strategies to deal with extremes of heat and cold, pollution and from being trampled underfoot. Lecanora dispersa is a species of lichen that can survive on pavements as it tolerates high levels of sulphur dioxide in the air. In the city it is black, but in rural areas it is white. Sow thistle, a yellow-flowered member of the daisy family is a plant that can survive extremes of temperature. Low-lying plants such as the dandelion and knotweed rapidly recover from being trampled on. Slugs, earthworms and centipedes, that hide under rocks in rural areas, escape under paving stones in the city. And as condensation forms on paving stones at night, slugs and earthworms come out to feed on the plants.
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Walls
Walls house a wide variety of different insects and other invertebrates. Ivy growing over these walls is home to many invertebrates, just as ivy found in any woodland is. Snails are commonly found on walls especially those made of limestone. Apart from shelter and food, the snail gets calcium carbonate for building its shell from the wall itself.
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