Sentences with phrase «species are fewer in number»

Small ecosystems are more vulnerable to extinctions; their member species are fewer in number and have limited refuge, and so are at statistically greater risk of being eliminated by a single event, whether a hurricane or the introduction of a predatory snake.

Not exact matches

With regard to pollinators, which greatly benefit from a richness of flowers, the fact that flowering weeds are more diverse and more abundant in organic arable fields and in organic grassland compared to conventional fields, where only few species and numbers were found, is particularly important.

«Larger - bodied species often need larger territories and are fewer in number than smaller - bodied species,» he explained, so they would have been more susceptible to extinction as hunting, logging, farming and other human activities took their toll.

Temperate waters are characterised by large numbers of a few species, tropical waters contain many species in relatively small numbers.

The refuge is located at the northern extent of dense leatherback nesting in Florida, but the species nest in far fewer numbers, laying just 23 nests in 2017 within the portion of the refuge monitored by UCF.

«In this study, we were interested in comparing different species of carnivorans to see how the numbers of neurons in their brains relate to the size of their brains, including a few favorite species including cats and dogs, lions and brown bears,» said Associate Professor of Psychology and Biological Sciences Suzana Herculano - Houzel, who developed the method for accurately measuring the number of neurons in brainIn this study, we were interested in comparing different species of carnivorans to see how the numbers of neurons in their brains relate to the size of their brains, including a few favorite species including cats and dogs, lions and brown bears,» said Associate Professor of Psychology and Biological Sciences Suzana Herculano - Houzel, who developed the method for accurately measuring the number of neurons in brainin comparing different species of carnivorans to see how the numbers of neurons in their brains relate to the size of their brains, including a few favorite species including cats and dogs, lions and brown bears,» said Associate Professor of Psychology and Biological Sciences Suzana Herculano - Houzel, who developed the method for accurately measuring the number of neurons in brainin their brains relate to the size of their brains, including a few favorite species including cats and dogs, lions and brown bears,» said Associate Professor of Psychology and Biological Sciences Suzana Herculano - Houzel, who developed the method for accurately measuring the number of neurons in brainin brains.

«According to our framework, under harsh conditions, only a few tolerant species can grow large populations, while the remaining and sensitive species can be present in low numbers, likely due to chance immigration.

If fact, some researchers believe a larger number of species are to be found in the Wheeler and Marjum Formations of Utah than in the Burgess Shale, though the fossils of soft - bodied animals in Utah are far less abundant and limited to relatively few horizons.

Over the next few years genes from different bacterial (and eventually mammalian) species were cloned into plasmids and new cloning vectors such as pBR322, pACYC, and pUC were developed to provide higher copy number vectors that could be used in these cloning experiments.

Background: Small non-coding RNAs, including miRNAs, and gene silencing mediated by RNA interference have been described in free - living and parasitic lineages of flatworms, but only few key factors of the small RNA pathways have been exhaustively investigated in a limited number of species.

This long tank houses a number of species of tangs, dwarf angelfish and a few Percula clownfish of different colorations, which have been developed in the past few years of captive breeding from the original orange with white stripe variety, including black and Picasso.

Some pinniped species, especially California sea lions and elephant seals, appear to be increasing in abundance while others like harbor seals may be fewer in number around the islands than they were in the past.

The ancient species had numbered more than a million a century ago and — in a crash similar to that of the American bison in the 19th century — was reduced to a few tens of thousands of animals at its nadir.

Not the point as the early raptor blenders were selectively killing species that occur in fewer numbers than, say, house sparrows.

But the minkie whale was not much hunted until recently, and several other species have greatly recovered in numbers following the excessive hunting of the last few centuries.

«Although many corals are becoming less abundant, there remain a number of species that are holding their own or increasing in abundance and these corals will populate tropical reefs over the next few centuries,» researcher Peter Edmunds, of California State University, explained.

As early as 1958, pioneer ecologists were marking out areas of forest — usually a hectare in size — and returning every few years to record the size, number and species of the trees found there.