Sentences with phrase «estimate population size»

Nest counts are the main source of demographic data for sea turtles, but it's hard to estimate population size from these counts.

Last, we used our livetrapping efforts to estimate the population size of feral cats on Catalina Island.

Nest counts are the main source of demographic data for sea turtles, but it's hard to estimate population size from these counts.

Co-author David Green, research faculty in OSU's Institute for Natural Resources, created the model that estimated the population size.

Clarifying population structure and genetic diversity can help in estimating population sizes and crafting management strategies.»

This is an integral part of conservation as it enables scientists to identify individuals and estimate population sizes.

Multilocus methods for estimating population sizes, migration rates and divergence time, with applications to the divergence of Drosophila pseudoobscura and D. persimilis

(b) By optimizing the likelihood of the data under the model, we can estimate population sizes and split times.

The estimated population size assumes that only 50 % of the interior population was trapped in a given year.

Not exact matches

The figure of 42,000,000 for China and Korea is based on the estimates as to the size of the Muslim community before the present government came into power, with a conservative allowance for population increase.

Subica and his colleague, Li - Tzy Wu, a professor at Duke University Medical Center, took on the project in part because national estimates of Pacific Islander, American Indian, and multiracial adolescent substance use and suicidality are scarce, presumably due to their small population sizes.

By reading thousands of alleles and estimating mutation rates, the duo can work out the separation date for each allele and calculate past population sizes.

Without knowing the size of the overall postdoc population, it is impossible to state the response rate and thus to estimate the degree to which the responses are representative.

But those estimates aren't reliable, as DNA isn't a good record of population size, says Allentoft.

This suggests that the Neanderthal population size once was much bigger than that estimated for the final stage of their existence.

The lack of reliable estimates of the population size and rates at which people enter and leave the postdoctoral pool complicated the analysis.»

By examining bits of DNA called microsatellites, which mutate rapidly, Goossens was able to trace individual genetic differences back to a common ancestor and estimate the size of the orangutan population at different times in the past.

To estimate changes in the size of the orangutan population over time, Voigt, along with Serge Wich from Liverpool John Moores University in the UK and their colleagues representing 38 international institutions, compiled field surveys conducted from 1999 to 2015.

Last year, FWS biologists estimated the population of Mexican wolves at 109 animals, the highest it's been since reintroduction and double its size in 2010.

Most estimates of historic whale population size have been extrapolated from old whaling figures, but this method is often very inaccurate, argues marine biologist Steve Palumbi of Stanford University's Hopkins Marine Station in California, US.

When he plugged in estimates of prehistoric population sizes and densities, he found that the ideal demographic conditions for advancement began in Africa 100,000 years ago — just when signs of modern behavior first emerge.

As for how many people the planet can sustain, the first such estimate came from microbiologist Anton van Leeuwenhoek who calculated roughly 13.4 billion people back in 1679, based on the population density of his native Holland and its size relative to the rest of the globe.

The scientists estimate that these gene variations were able to persist in Neanderthals because Neanderthals had a much smaller population size than humans.

«Even allowing that our estimate of the trans - Neptunian population is uncertain by a factor of several,» write Jewitt and Luu, «it is clear that these distant objects vastly outnumber the main - belt asteroids of comparable size.»

American Oystercatcher (Haematopus palliates) nests are sparsely distributed, time - intensive to find, and often in remote locations, all adding to the challenge of estimating the size of their breeding population.

A new study from The Condor: Ornithological Applications provides the first direct estimates of the population size and annual survival of young birds in Oahu's Laysan Albatross population, giving important new insights into the demographics of these «prebreeders.»

Estimates of the population size at its nadir range from 30,000 to 200,000.

In the subsequent Marine Mammal Science paper just out, the catches were among the key pieces of information used to model the size of the California blue whale population over time — a model previously used by other groups to estimate populations of hundreds of fish and various other whale species.

The new estimates suggest that proposals to lift the International Whaling Commission's 18 - year - old moratorium on commercial whaling are based on a faulty assessment of what constitutes natural population sizes.

Oppel and his team found that they could use audio recordings to estimate a bird's population size after testing the method on a raucous colony of Cory's shearwaters that breeds on a small island in the Azores called Corvo.

Instead, estimates are based mainly on the size and variability of past populations in a specific area.

Faced with these uncertainties, Levison and his group did choose somewhat conservatively from the available population estimates, picking a relatively small figure for the size of the Oort Cloud and a large one for the scattered disk.

The researchers also estimated ancient Denisovan population sizes by using methods to estimate the age of various gene lineages and the amount of difference between the chromosomes the girl inherited from her mother and father.

Weiskopf explained that a big problem with collecting and identifying scat in the field is that researchers mostly rely on morphological characteristics such as shape, size or associated signs of snow leopards, and since scat from different species can look similar, this can lead to misrepresented population estimates and errors in reporting what the snow leopards are actually eating.

The cat recently surpassed the dog as the most popular pet in the world, with a global population size estimated at 600 million.

In 1990, The total population size was estimated at 1.5 million, however, more recent estimates put the population at over 4 million.

To estimate the size of the species population, these citizen scientists visit 200 coastal sites over the course of three weeks where butterflies spend their winters.

The passenger pigeon was once the most abundant bird in the world, with a population size estimated at 3 — 5 billion in the 1800s; its abrupt extinction in 1914 raises the question of how such an abundant bird could have been driven to extinction in mere decades.

Applying high - throughput sequencing technologies to obtain sequences from most of the genome, we calculated that the passenger pigeon's effective population size throughout the last million years was persistently about 1/10, 000 of the 1800's estimated number of individuals, a ratio 1,000 - times lower than typically found.

The snow leopard population size was estimated independently for each year.

We estimated the neutral mutation parameter (4Neμ for autosomal loci and 3Neμ for X-linked loci), where Ne is the effective population size and μ is the mutation rate per site per generation, using two estimators: Watterson's θw [67], the proportion of segregating sites in a sample, and π [68], the average number of pairwise differences per sequence in a sample.

We therefore used this information for estimating annual adult sex ratios, but did not use it to estimate additional population parameters due to further fragmentation of the small sample size.

Estimates of current and ancestral population sizes (Ne1 = 1,600,000; Ne2 = 780,000; Nancestral = 470,000), divergence time (1,800,000 years and assuming a generation time of 1 year), and gene flow (2Nm1autosomal = 1.69; 2Nm2autosomal = 0.83; 2Nm1X - chromosome = 0.38; 2Nm2X - chromosome = 0.26) were obtained from previous studies and inferred using an Isolation - with - Migration model [21], [26].

(c) Applied to hundreds of European individuals, rarecoal estimates split times as indicated on the time axis and population sizes for each branch.

Aggregate effects on IGF and its BPs were estimated by multivariate regression on macronutrient sources from dietary questionares and blood samples in 4700 + subjects, but the effect sizes were small and the only protein source where a statistically significant effect was seen was with dairy protein and dietary calcium (ie associated with dairy in general population cohorts).

Its size is 344 km with an estimated population of 110,000.

Its size is just over 112,000 km with an estimated population of almost 8,000,000.

Its size is just under 110,000 km with an estimated population of 14,000,000.

With an estimated 600,000 Iranians and 400,000 Armenians in LA — the largest populations outside those countries — the sheer size of the communities is fueling much of the growth.

The task can be done by asking the pupils to estimate the size of the city first and then using this website to found the populations http://www.citypopulation.de/UK-Cities.html, or alternatively there is a worksheet with the populations written, if you do not want to use the website.