Sentences with phrase «population bottlenecks»

Previous analyses using mtDNA RFLP's identified more mtDNA haplotypes than detected by our whole mitogenome (WMG) sequencing analysis on San Miguel (2 RFLP: 1 WMG genotypes) and Santa Catalina (3 RFLP: 2 WMG genotypes), suggesting a possible loss of mtDNA diversity on these islands as a result of population bottlenecks over the past 25 years [15].

This massive environmental change is believed to have created population bottlenecks in the various species that existed at the time; this in turn accelerated differentiation of the isolated human populations, eventually leading to the extinction of all the other human species except for the branch that became modern humans.

The invariance likely results from either a recent selective sweep, a recent origin for modern Homo sapiens, recurrent male population bottlenecks, or historically small effective male population sizes.

The findings «more firmly document» a Finnish population bottleneck, says Markku Linnoila, a psychiatrist at the National Institute on Alcohol Abuse and Alcoholism.

The natives passed through a second population bottleneck, losing 90 percent of their numbers, then rebounded during the 20th century.

An ancient population bottleneck has resulted in genetic uniformity and has made the species extremely vulnerable to ecological change

They found a similar amount of harmful mutations among different snub - nosed monkeys as well as reduced genetic diversity compared to other primates, which is indicative of having suffered a severe population bottleneck or possible inbreeding.

«The Middle Stone Age (MSA) is associated with early behavioral innovations, expansions of modern humans within and out of Africa, and occasional population bottlenecks.

To this end, his work often relies on anthropology and human history as much as it does on genome sequencing and computation, in order to decipher the subtle genetic signatures that appear when species undergo major events such as population bottlenecks, large - scale migration or dispersal events, or the development of resistance to disease.

The combination of introgression and past population bottlenecks suggested that basal breeds have little or no genetic connections to their ancestral populations and that their genetic distinctiveness does not signify ancient heritage.

The loss of genetic diversity in purebred dogs can be attributed to two major population bottleneck events: the first occurring during domestication; and the second arising from breed formation where the repeated use of popular sires, line breeding, breeding for specific phenotypic traits, and promotion of the breed barrier rule, contributed to overall loss in genetic variation [15 - 19].

Elephant seal genetic variation and the use of simulation models to investigate historical population bottlenecks.

This scenario is supported by similarities between these islands in morphological and mtDNA restriction hybridization data collected before 1990 and the later fox population bottlenecks [15,20].

Little scraps of ingenuity like this might one day link together with a backbone of grand technological advancement to ensure that our civilization passes through the climate - energy - population bottleneck unscathed and with an economy that is still growing (sustainably).

These estimates suggest a very recent and rapid expansion of modern polar bear populations throughout the Arctic since the Late Pleistocene, perhaps following a climate - related population bottleneck, although data from more modern and Holocene polar bear specimens will be required to establish this.

Simulations demonstrate that significant genetic differences observed between ancient and modern samples could be caused by a large, recent population bottleneck, roughly concurrent with commercial whaling.

In this regard, recent diachronic aDNA analyses of Central European populations have documented a fluctuation in haplogroup frequencies as a result of population bottlenecks and post-Neolithic migratory events [19], [20].

Do a bit of study regarding genetic drift, population bottlenecks and the impossibility of the entire human race having come from 3 breeding pairs of humans, with all the males being 1st order relatives, a mere 4,000 years ago.

To understand the population bottlenecks during domestication, researchers made a comparison analysis between vegetable and grain food crops.

It was at a time when there was a population bottleneck, which means a sharp reduction in the number of living individuals due to environmental events.

Sundell, T., Kammonen, J., Halinen, P., Pesonen, P. & Onkamo, P. Archaeology, genetics and a population bottleneck in prehistoric Finland.

This created a population bottleneck.

Using rejection - based Approximate Bayesian Computation, we estimate the size of the population bottleneck at its minimum abundance and the pre-bottleneck abundance.

Though our ability to infer what was surely a complex demographic history is limited by the number of ancient samples available and large uncertainties associated with the coalescent and evolutionary processes, these first ancient data for gray whales demonstrate the value of paired genetic and isotopic studies of ancient samples, showing that a population bottleneck can result in significant genetic differentiation between ancient and modern samples without requiring spatial structure.

Tagged Arctic basin, genetic bottleneck, ice age, last glacial maximum, LGM, perennial ice, Pleistocene, polar bear, population bottleneck, population decline, ringed seal, sea ice, sea ice habitat, sea level, seasonal ice

Our ancestors lived through hundreds of such abrupt episodes since the more gradual Ice Ages began two and a half million years ago — but abrupt cooling produced a population bottleneck each time, one that eliminated most of their relatives.

Our ancestors lived through hundreds of such episodes — but each became a population bottleneck, one that eliminated most of their relatives.