Animal populations with impoverished genetic diversity are inherently less able to adapt to changes in their environment ( such as climate change, disease outbreaks, habitat change, etc .).

The principle becomes quite complex, however, given the uncertainties of fossilization, the localization of fossil types due to lateral changes in habitat ( facies change in sedimentary strata ), and that not all fossils may be found globally at the same time.

Escapees can adversely impact local ecosystems through hybridization and loss of genetic diversity in native stocks, increase negative interactions within an ecosystem ( such as predation and competition ), disease transmission and habitat changes ( from trophic cascades and ecosystem shifts to varying sediment regimes and thus turbidity ).

The blue wildebeest changed very little from the ancestor species, while the black wildebeest took on more morphological changes to adapt to a habitat of open grassland in the south.

Overall, in the 1996 – 2006 period, the number of hunters over the age of sixteen declined by ten percent, a drop attributable to a number of factors including habitat loss and changes in recreation habits.

Most observed effects are due not to toxicity, but to habitat changes and the decreases in abundance of species on which birds rely for food or shelter.

The diversity of subspecies is probably the product of a largely Early Pleistocene radiation aided by climate and habitat changes during the last ice age.

The species is not the only pigeon to have increased its range due to the actions of man ; several other species have become established outside of their natural range after escaping captivity, and other species have increased their natural ranges due to habitat changes caused by human activity.

Edge effect can cause changes in abiotic and biotic conditions which can cause the natural variation to be lost and make the habitat unsuitable for the original ecosystem.

The evolutionary change is thought to be a result due to the changes in habitat over time.

Over periods of ecological changes, biogeography includes the study of plant and animal species in: their past and / or present living refugium habitat ; their interim living sites ; and / or their survival locales.

Biodiversity loss occurs in wetland systems through land use changes, habitat destruction, pollution, exploitation of resources, and invasive species.

It is possible that this extinction occurred as a direct result of hunting, but was more probably a result of widespread habitat changes brought about by human activities — notably the use of fire.

For example, almost any land habitat offers a nice home for a small bird that specialises in finding small insects: the form best fitted to that task is one with long legs for agility and obstacle clearance, moderately-sized wings optimised for quick, short flight, and a large, upright tail for rapid changes of direction.

Some cockatoo species have been adversely affected by habitat loss, particularly from a shortage of suitable nesting hollows after large mature trees are cleared ; conversely, some species have adapted well to human changes and are considered agricultural pests.

Bird movements include those made in response to changes in food availability, habitat, or weather.

The Shoebill is non-migratory with limited seasonal movements due to habitat changes, food availability and disturbance by humans.

In some areas, migration routes have changed due to changes in habitat and food sources.

The Baillieu State government has proposed changes to allow loggers to ignore existing protected species legislation in future, virtually signing the death warrant of the Leadbeater's possum ( this follows the success of other recent cases preventing logging of remaining possum habitat ).

The Eastern or Chinese Spot-billed Duck is currently introgressing into the Mallard populations of the Primorsky Krai, possibly due to habitat changes from global warming.

It is native to eastern North America and has shown reduction in numbers and increasing hybridization with the more common Mallard as that species has spread with man-made habitat changes.

Several studies suggest that the landscape has critical thresholds at which ecological processes will show dramatic changes, such as the complete transformation of a landscape by an invasive species with small changes in temperatures which favors the invasive's habitat requirements.

Some of the primary factors contributing to this decline are habitat loss, contaminants, changes in breeding habitat, and a lower female survival rate.

For example, on Saint Lucia, harvesting mangrove for timber and clearing for fishing reduced the mangrove forests, resulting in a loss of habitat and spawning grounds for marine life that was unique to the area.

Degraded water quality, habitat loss resulting from impoundments, ore and gravel mining, sedimentation, and collection for the pet trade are thought to be the main factors resulting in the amphibian's decline.

The clearance of large tracts of land for crop growth has led to a significant reduction in the amount available of forestation and wetlands, resulting in the loss of habitat for many plant and animal species as well as increased erosion.

The primary threats to red pandas are direct harvest from the wild, live or dead, competition with domestic livestock resulting in habitat degradation, and deforestation resulting in habitat loss or fragmentation.

Herpetoculturists respond that with few exceptions, wild collecting is incidental and trivial compared to the losses resulting from habitat destruction and modification, highway mortality, and killing by people out of fear or ignorance.

Rugged mountains more than 7, 000 ft ( 2150 m ) in elevation west of the area create a pronounced rain-shadow effect, resulting in a shrub-steppe habitat zone with annual rainfall of less than.

North of Esher the old river channel is dominated by floating pennywort, a highly invasive weed, which cuts off all light to the river bed, reducing oxygen levels and resulting in a poor habitat for fish.

In the UK, the Hen Harrier suffers illegal persecution by gamekeepers and their employers on shooting estates, particularly those managed for Red Grouse shooting, resulting in local and regional extinction in many areas, particularly in England where only 4 breeding pairs survive despite abundant suitable habitat capable of holding several hundred pairs.

Their ability to adapt to a large variety of habitats has allowed for their dispersal and establishment throughout the world — resulting in a habitat range from coastal wetlands to alpine forests, from sea level to 1900 metres above sea level.

Once their habitat is destroyed, they cease to exist. This destruction has a follow-on effect, as species which coexist or depend upon the existence of other species also become extinct, eventually resulting in the collapse of an entire ecosystem.

Australia has large P. radiata plantations ( though they are less than 2 % of the total forested area ); so much so that many Australians are concerned by the resulting loss of native wildlife habitat.

Since high flow rates occur during storm events, the resulting floods tend to scour the bottom of the river which reduces fish habitat.

# Reaction: During this phase autogenic changes affect the habitat resulting in replacement of one plant community by another.

The concerns for the natural environment include damage to ecosystems and loss of habitat resulting from population growth, expansion of subsistence agriculture, pollution, timber extraction and significant use of timber as fuel.

The major threat facing the Asian elephant today is habitat loss resulting from deforestation.

* an ecotone describes a variation in species prevalence and is often not strictly dependent on a major physical factor separating an ecosystem from another, with resulting habitat variability.

One of the key elements of a sky island is separation by sheer physical distance from the other mountain ranges, resulting in a habitat island, such as a forest surrounded by desert.

According to Seafood Watch, monkfish consumption raises sustainability concerns due to past overfishing and damage to the seafloor habitat resulting from the use of trawlers and gillnets to catch this fish.

A devastating fire in July 1995 burned large portions of these mountains, resulting in the loss of significant forest land and natural habitat.

The bottom-release design of the dam allows for the discharge of a cold water at a constant temperature, resulting in an ideal habitat for rainbow trout and brown trout, which are stocked annually in the stream.