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Biologists analyzed data from 2,600 lizard species worldwide and discovered that, while hundreds of different types of lizards have independently evolved arboreal lifestyles, species that possessed st...
New way to identify disease-resistant genes in chocolate-producing trees（图）
New way disease-resistant genes chocolate-producing trees
2019/12/13
Chocolate-producing cacao trees that are resistant to a major pathogen were identified by an international team of plant geneticists. The NSF-funded finding points the way for plant breeders to develo...
Striped maple trees often change mating types, with females more likely to die（图）
Striped maple trees change mating types females likely to die
2019/10/28
More than 90 percent of flowering plant species combine male and female characteristics in one plant. In the less than 10 percent where female and male flowers exist on separate plants, they typically...
Researchers invent a breakthrough process to produce renewable car tires from trees and grasses
Researchers breakthrough process produce renewable car trees grasses
2017/3/13
A team of researchers, led by the University of Minnesota, has invented a new technology to produce automobile tires from trees and grasses in a process that could shift the tire production industry t...
Study:Alaskan boreal forest fires release more carbon than the trees can absorb
Alaskan boreal forest fires carbon trees
2015/11/12
A new analysis of fire activity in Alaska's Yukon Flats finds that so many forest fires are occurring there that the area has become a net exporter of carbon to the atmosphere. This is worrisome, the ...
Variation in demersal fish species richness in the oceans surrounding New Zealand:an analysis using boosted regression trees
Demersal fish Species richness Boosted regression trees Statistical model
2015/8/21
We analysed relationships between demersal fish species richness, environment and trawl characteristics using an extensive collection of trawl data from the oceans around New Zealand. Analyses were ca...
A working guide to boosted regression trees
data mining machine learning model averaging random forests species distributions
2015/8/21
A working guide to boosted regression trees.
Fruits of the forest gone: Overhunting of large animals has catastrophic effects on trees（图）
Overhunting large animals catastrophic effects trees
2014/12/1
The elephant has long been an important spiritual, cultural and national symbol in Thailand. At the beginning of the 20th century, its numbers exceeded 100,000.
University of California, Berkeley, geologist William Dietrich pioneered the application of airborne LIDAR – light detection and ranging – to map mountainous terrain, stripping away the vegetation to ...
Experts advocate for stronger measures to protect trees and other plants from pests and pathogens
Experts advocate stronger measures protect trees other plants pests and pathogens
2013/5/27
As the fungus responsible for ash dieback continues to devastate ash tree populations throughout the UK and other threats to the countryside continue to emerge, experts convened by Defra are advocatin...
Dyadic groups, dyadic trees and symmetries in long nucleotide sequences
genetic code alphabet dyadic group dyadic shift hypercomplex numbers dual numbers bicomplex numbers
2012/5/2
The conception of multi-alphabetical genetics is considered. Matrix forms of the representation of the multi-level system of molecular-genetic alphabets have discovered algebraic properties of this sy...
A Unified Framework for Trees, Multi-Dimensional Scaling and Planar Graphs
Unified Framework for Trees Multi-Dimensional Scaling Planar Graphs
2011/1/5
Least squares trees, multi-dimensional scaling and Neighbor Nets are all different and popular ways of visualizing multi-dimensional data. The method of flexi-Weighted Least Squares (fWLS) is a powerf...
What use are Exponential Weights for flexi-Weighted Least Squares Phylogenetic Trees?
Exponential Weights flexi-Weighted Least Squares Phylogenetic Trees
2011/1/5
The method of flexi-Weighted Least Squares on evolutionary trees uses simple polynomial or exponential functions of the evolutionary distance in place of model-based variances. This has the advantage ...
The algebra of the general Markov model on phylogenetic trees and networks
general Markov model phylogenetic trees
2011/1/5
It is known that the Kimura 3ST model of sequence evolution on phylogenetic trees can be extended quite naturally to arbitrary split systems. However, this extension relies heavily on mathematical pec...
An algebraic analysis of the two state Markov model on tripod trees
algebraic analysis Markov model tripod trees
2011/1/5
Methods of phylogenetic inference use more and more complex models to generate trees from data. However, even simple models and their implications are not fully understood. Here, we investigate the tw...