Sentences with phrase «reproductive rates»

These kill rates can't go on much longer because sharks have a very low reproductive rate.

And with one of the highest reproductive rates in the animal kingdom, this isn't a great leap of logic.

Their short life span and fast reproductive rate, makes it possible to investigate biological processes in many subjects, at all stages of the life cycle.

The western harvest mouse has a high potential reproductive rate.

Novelist Michael Crichton, in State of Fear, ends with an appendix comparing the theory of global warming to the theory of eugenics — the belief, prominently promoted by Nazis, that the gene pool of the human species was degenerating due to higher reproductive rates of «inferior» people.

According to Lee, elephants exhibit the classical mammalian pattern of a decline in reproductive rate after age 49, followed by up to sixteen years of post-reproductive survival.

These factors, along with an inherently slow reproductive rate, continue to threaten the remaining Hawaiian monk seal population.

So while elephant calves clearly get a major survival and reproductive benefit from having a living grandmother, the females do not exhibit classical forms of menopause — or cessation of reproduction long before death — seen in whales and humans, despite having an average of a 16 - year period between when a long - lived female's reproductive rate declines and her own death.

They also have different reproductive rates.

Hopefully, Vasalgel placement can be an option for other captive colonies, including zoos, that want to manage reproductive rates while allowing for social housing.»

They compared lifetime reproductive variation in females from 31 Tanzanian lion prides to the variation in simulated prides, in which reproductive rate and demography were the same as in the real prides but births were randomly allocated.

Worse yet, smaller females are less fertile than large ones, meaning the few remaining females have suboptimal reproductive rates.

Small - bodied species, with rapid reproductive rates, dominated post-extinction communities, despite the presence of many successful large - bodied species before the extinction.

The authors have also estimated the so - called reproductive rate of the virus in each country, which represents the average number of people that each infected person in turn infects.

When shielded from blue light, however, the bugs» reproductive rate dropped by more than 90 %, the team reports in tomorrow's issue of Science.

Typical for most insects, a single female of sawflies and parasitic wasps, which represent the earliest branches in the phylogeny, can lay hundreds of eggs during her lifetime, but the more advanced solitary nest - provisioning Hymenoptera can rarely lay more than a dozen (reviewed in O'Neill [3]-RRB- with some species having even lower reproductive rates [4].

As a first step, the report recommends «building affordable surveillance systems» to detect population changes, including reproductive rates, which can be a simple indicator of a species» health.

Their results suggest several inherent ecological traits that likely contribute to vultures» extinction risk, including their large body masses, slow reproductive rates and highly specialized diets.

For long - lived species such as humans, chimpanzees, whales and some birds, longer survival is associated with higher reproductive rates and a loss in fertility only at an extremely old age.

Actually, there are scientists who have presented studies showing that TNR decreases colony size — i.e., showing that in - migration does not make up for the reduced reproductive rate.

Because mutations happen when Avidians copy themselves, which lead to differences in reproductive rates, these digital organisms evolve, just like living things.

Most social conservatives know that the main determinant of reproductive rates in America isn't patriotism but religion.

While I generally agree, if OBL gets any virgins, they must be children, because based on their reproductive rates I am QUITE sure you couldn't find 20 adult Muslims who still had the trait.

In other words, to acheive such a reproductive rate, a woman would have to have a child every 3.3 years every year from 15 — 45.

The new study, published in the journal Proceedings of the National Academy of Sciences, compares data from 166 wildlife surveys conducted across the Amazon basin to estimate the impact of hunting on game species with low reproductive rates, such as primates.

When they compared the reproductive rates at the two sites, by scoring the number of pregnant females shot, they found that peccaries in the intensely hunted region kept their numbers up by reproducing more often.

The researchers used a global distribution map of these species, included data on their morphology and reproductive rate, and estimated predation rate.

Bat populations are generally susceptible to decline because of low reproductive rates, and many species congregate at a limited number of locations during critical stages of their natural history cycle (i.e. hibernacula and maternity colonies).

Mountain lions occur at far lower densities than deer, and so any loss of their prey can have disporportionate impacts on their reproductive rates and overall abundance.»

You see the effect of this in reproductive rates, with the month of June showing the highest rate of conception.

Fisheries quotas, even though they were responsibly set and followed by fishers, decreased the reproductive rate.

«The reproductive rate, at least in Sierra Leone and Liberia, was higher at the beginning of the epidemic.

That's true in Alberta, Canada, where the bears, already low in number, have been threatened by habitat loss and human hunters and have low reproductive rates.

But whale sharks can not replenish their numbers under heavy fishing pressure because of the species» long life span, slow reproductive rate, naturally low abundance, and highly migratory nature.

Some of the things that have yet to be conclusively proved include why right whales have periodically disastrous low reproductive rates but sometimes recover; or how whales arrive at feeding grounds that other whales have found.

«Daughters of long - lived mothers lived longer themselves and had higher reproductive rates.»

As the authors also observed in previous works, some aphids showed different chromosome numbers also comparing cells belonging to a same individual «forgetting» that chromosome instability within individuals should be typical of malignant cells and not of healthy insects showing a high reproductive rate.

«Not acting is not an option because the life histories of these flying, nocturnal mammals — characterized by long generation times and low reproductive rates — mean that population recovery is unlikely for decades or even centuries, if at all,» said McCracken.

Our current analyses of the Passenger Pigeon's breeding success in the final stages of its decline indicate that the species» reproductive rate was not affected by low numbers and flock fragmentation.

What most people don't tend to understand is that, based on the sheer number and reproductive rates, the overall contribution of unowned free - roaming cats to cat overpopulation is much greater than owned cats, and this is what needs to be curtailed.

Given these high reproductive rates, it stands to reason that, in only a few years, carefully planned and implemented sterilization programs could produce a dramatic reduction in the number of unwanted companion animals born.

Given these high reproductive rates, it stands to reason that carefully planned and implemented sterilization programs could produce a dramatic reduction in the number of unwanted companion animal births in only a few years.

In another contrast with other canids, the reproductive rate was lower for captive - born island foxes, the opposite of what is usually observed in other canid species.

Though wild dogs can often recover faster from population decreases due to their high reproductive rate, the researchers concluded that such practices place added pressure on species that are already suffering from habitat loss and restricted ranges and require further action to monitor and minimize.

Rising temperatures due to global warming have boosted the beetles» numbers by increasing their reproductive rate and reducing their winter die - off.

«Its strategy for survival is based on a high reproductive rate, so [the Saiga] produce triplets and have the highest fetal biomass of any mammal.