Sentences with phrase «small isolated populations»

Consequently, they exist only in small isolated populations and there are less than 500 wild nesting females in total.

The researchers suggest to resettle small isolated populations and to undertake measures to improve fertility.

«Females do not find a mating partner within the small isolated populations any more,» explains Petra Kretzschmar, scientist at the Leibniz Institute for Zoo and Wildlife Research (IZW), «the long non-reproductive periods lead to the development of reproductive tract tumours.»

Change can also occur due to accidental loss of alleles (genetic drift) in small isolated populations.

In contrast, smaller isolated populations are genetically decoupled from the mitigating effects of gene flow can rapidly radiate.

Not exact matches

So, this isn't a problem that is isolated to a small subsection of our population but is probably something ingrained within our psyche.

It happens over generations as later generations stay in many ways quite similar but in certain respects become rather different from earlier generations, especially in small, isolated populations facing novel selection pressures.

See Appendix A. 1 for more information * There are a number of broad Australian comparative disadvantages such as high labour costs, a dispersed and geographically isolated market and small population which impact the MTP sector.

The Andromeda Galaxy is easily visible to the naked eye in a moderately dark sky, though such a sky is available only in smaller towns and isolated areas reasonably far from population centers and sources of light pollution.

Though wolves are on the upswing in these regions, their populations are likely too isolated to control the pervasive coyote and other small predators.

Kiessling says reefs may be so prolific because their complexity can support greater variety, more frequent extinctions provide opportunities for new species and their nutrient - poor waters keep populations small and isolated, making them more likely to diverge into new species.

«Small populations in isolated patches can be easily lost and, in a warmer climate, could simply die out,» she warns, adding that Southern Appalachia trout fishing may become «heavily managed.»

Specifically, Toni Gabaldón's group at the Centre for Genomic Regulation in Barcelona has compared the Iberian lynx genome with those of other species, attempting to identify genes that have lost their function because they have remained isolated and the existence of a small population of specimens of this species.

This genetic deterioration is especially marked in the Doñana population - smaller, and isolated for a longer period - which has half the genetic diversity of the Sierra Morena group.

Most scientists believe a small and isolated population in Africa must have been infected with HIV decades or even centuries ago.

Later, in the 1990s, researchers turned up a small set of isolated, inbred populations scattered over a wide region.

The use of cell surface markers to isolate specific cell populations is one common method for separating cells; however, isolating live cells based on their RNA expression is a powerful new way enabling the study of small cell niches in nongenetically modified animal models and human tissue.

«Because these populations are very small and often isolated, they are incredibly sensitive to over-collecting,» added Minteer, also the Arizona Zoological Society Chair at ASU.

The genetic data indicates that the Ashkenazi Jewish population was founded in the late medieval times by a small number, effectively only hundreds of individuals, whose descendants expanded rapidly while remaining mostly isolated genetically.

For thousands of years our ancestors lived in small, isolated populations, leaving them severely inbred, according to a new genetic analysis.

I just started working on my Ph.D. in engineering in a town with a very small minority population, and I feel extremely isolated and alone.

«In terms of practical nature conservation, these results signify that in the future it will no longer be sufficient to preserve small, isolated reserves — while these benefit specialized species with a simple genetic structure, the bulk of species that depend on an exchange between local populations will lose out in the medium to long term,» predicts Schmitt, and he adds in closing, «This will lead to a further decline of numerous insect species — with dramatic consequences for entire food webs and ecosystems.»

Small, isolated populations could be protected by amphibian - proof fences.

They found that almost all the samples were genetically similar, suggesting the cave bear population was small, isolated and therefore vulnerable.

Devils Hole is especially isolated, and the pupfish population there is particularly small, ranging from 35 to 548 fish in the remote cavern since official recordkeeping began in the 1970s.

Such small, isolated populations are essentially doomed: even if the forest fragments survive, sooner or later dwindling gene pools or disasters such as forest fires and disease outbreaks will wipe them out.

Because their populations are already small in the region, barriers that isolate bears could eventually lead to inbreeding, increasing the risk of local extinction over time.

«This study illustrates that there is a lot to be gained in human genetics by looking into small, isolated populations.»

After that heyday, the bears must have been split up into small, isolated populations — genetic bottlenecks — perhaps as they sought refuge on islands and other areas not covered by advancing glaciers during the most recent ice age.

It never recovered completely — probably, the team concludes, because changes in habitat, particularly forest growth, kept populations small and isolated from the southern herds, which had less severe declines in diversity.

Scientists are concerned that butterflies with small, isolated populations may be in severe peril if their habitats are burned too frequently and in large blocks at a time, which can mean that butterfly refugia — unburned areas that provide refuge — are limited.

The scientists have resolved a dispute over whether a small population of black - headed squirrel monkeys (Saimiri vanzolinii), which are found only in an isolated part of Brazil, is a sub-species of another species or its own species.

This genetic deterioration is especially marked in the Doñana population — smaller, and isolated for a longer period — which has half the genetic diversity of the Sierra Morena group.

By analyzing these two exomes together with the genome sequence of a Neandertal from Siberia we show that the genetic diversity of Neandertals was lower than that of present - day humans and that the pattern of coding variation suggests that Neandertal populations were small and isolated from one another.

Even if evolution were true, the island of Flores is too small to have maintained an isolated population for long enough to allow the evolution of a new species, say researchers at Pennsylvania State University (NewScientist, 26 August 2006, p. 7).

The genomes of both the Vindija and Altai Neanderthals provide evidence that Neanderthals lived in small and isolated populations of no more than about 3,000 individuals per region.

The Burrunan dolphin, Tursiops australis, has only recently been discovered but is already under threat due to its small and isolated populations.

Just as some traits (even metabolic traits) run in families so too will they run in populations, especially within rather small isolated tribal ones (they are less diverse).

However, dog breeds generally are characterized by closed breeding and relatively isolated populations, often with a small number of founders and popular sires whose gene pool is overrepresented in modern - day progeny.

Like any small, isolated island populations, the island fox remains extremely vulnerable to any catastrophic mortality source, be it predation, canine disease, or environmental extremes (1).

In a punctuationist model of speciation in Homo, the anatomical and cognitive adaptations unique H. sapiens would have evolved together in a small, isolated population of its parent species (currently thought to be H. heidelbergensis).

The important question is: How many of additional species living lonely lives in their isolated patches (the 5 %) would become extinct eventually because their population sizes are too small to be viable?

The result is relatively higher adaptation and disaster risk reduction costs per capita in countries with small populations and areas, especially those that are also geographically isolated, have a poor resource base and high transport costs

As pockets of forest habitat are isolated, their edges are exposed to harsher, brighter, drier conditions and plant and animal dispersal between habitat fragments is made more difficult; in addition, habitat fragments may be too small to sustain populations of some species.

The inquiry noted that Indigenous people make up a high proportion of the population in regional and remote districts with around 1,200 discrete Indig enous communities of which over 1,000 were very small and very isolated communities.61 Limited commercial opportunities and viable labour markets in these communities means that they often lack some of the most basic services, including access to banking and financial services and institutions.