A University of Kansas anthropological geneticist is part of an international research team working to shed light upon one of the unanswered questions concerning the peopling of the New World: Namely, what was the size of ...
Evolution
May 2, 2018
23
6527
A study by Canadian researchers is providing a clearer picture of the evolutionary history and genetic organization of cannabis, a step that could have agricultural, medical and legal implications for this valuable crop.
Plants & Animals
Aug 26, 2015
3
1636
Starting about 7,000 years ago, something weird seems to have happened to men: Over the next two millennia, recent studies suggest, their genetic diversity —specifically, the diversity of their Y chromosomes—collapsed. ...
Biotechnology
May 29, 2018
57
1689
In new research, Arizona State University scientists and their colleagues investigated genetic changes occurring in a naturally isolated population of the water flea, Daphnia pulex. This tiny crustacean, barely visible to ...
Evolution
Jul 15, 2024
0
298
A study of hundreds of new genomes from across the globe has yielded insights into modern genetic diversity and ancient population dynamics, including compelling evidence that essentially all non-Africans today descend from ...
Archaeology
Sep 21, 2016
15
3546
The extinction of prehistoric megafauna like the woolly mammoth, cave lion, and woolly rhinoceros at the end of the last ice age has often been attributed to the spread of early humans across the globe. Although overhunting ...
Archaeology
Aug 13, 2020
6
1842
Dramatically perched on an Andes mountain ridge some 8,000 feet above sea level in Peru, Machu Picchu is a visual wonder and a technical masterpiece.
Archaeology
Oct 1, 2015
4
956
Modern Eurasian sheep predominantly belong to only two so-called genetic matrilineages inherited through the ewes, so previous research has assumed that genetic diversity must already have decreased rapidly in the early stages ...
Archaeology
Apr 15, 2024
1
109
The myth that modern wheat varieties are more heavily reliant on pesticides and fertilisers is debunked by new research published in Nature Plants today.
Plants & Animals
Jun 17, 2019
10
1820
Brown University evolutionary biologist Sohini Ramachandran has joined with colleagues in publishing a sweeping analysis of genetic and linguistic patterns across the world's populations. Among the findings is that geographic ...
Social Sciences
Jan 20, 2015
7
2564
Genetic diversity is a level of biodiversity that refers to the total number of genetic characteristics in the genetic makeup of a species. It is distinguished from genetic variability, which describes the tendency of genetic characteristics to vary.
The academic field of population genetics includes several hypotheses and theories regarding genetic diversity. The neutral theory of evolution proposes that diversity is the result of the accumulation of neutral substitutions. Diversifying selection is the hypothesis that two subpopulations of a species live in different environments that select for different alleles at a particular locus. This may occur, for instance, if a species has a large range relative to the mobility of individuals within it. Frequency-dependent selection is the hypothesis that as alleles become more common, they become less fit. This is often invoked in host-pathogen interactions, where a high frequency of a defensive allele among the host means that it is more likely that a pathogen will spread if it is able to overcome that allele.
This text uses material from Wikipedia, licensed under CC BY-SA
