نتایج جستجو برای: related diversification

تعداد نتایج: 1185807  

Journal: :IOP conference series 2022

Abstract Activities in the agricultural sector are always faced with risk and uncertainty. The problem of uncertainty is also experienced by vegetable farmers Marelan District. Generally, cultivate long beans, spinach, mustard. One alternative that can be done to minimize impact doing diversification. Moreover, diversification supports sustainability agriculture. Diversification farming combini...

2010
James A. Fordyce

BACKGROUND Phylogenetic hypotheses are increasingly being used to elucidate historical patterns of diversification rate-variation. Hypothesis testing is often conducted by comparing the observed vector of branching times to a null, pure-birth expectation. A popular method for inferring a decrease in speciation rate, which might suggest an early burst of diversification followed by a decrease in...

Journal: :E3S web of conferences 2021

The paper considers the problems of choosing strategies for diversifying companies. It was revealed that in corporate practice, there is a certain tendency towards moderately diversified companies with related business lines (relational diversification). authors analyzed set four main growth strategies: market penetration; expansion; product innovation, and diversification. Their advantages dis...

2012
Wenhua Yu Junxiao Xu Yi Wu Guang Yang

Although mammals have long been regarded as a successful radiation, the diversification pattern among the clades is still poorly known. Higher-level phylogenies are conflicting and comprehensive comparative analyses are still lacking. Using a recently published supermatrix encompassing nearly all extant mammalian families and a novel comparative likelihood approach (MEDUSA), the diversification...

2006
Daniel L Rabosky

Rates of species origination and extinction can vary over time during evolutionary radiations, and it is possible to reconstruct the history of diversification using molecular phylogenies of extant taxa only. Maximum likelihood methods provide a useful framework for inferring temporal variation in diversification rates. LASER is a package for the R programming environment that implements maximu...

2008
Sanzidur Rahman

This study aimed at examining the merit of crop diversification as a strategy for agricultural growth in Bangladesh. Specifically, the existence of economies of diversification, scale economies and diversification efficiencies at the farm level were examined using a stochastic input-distance function approach. Results reveal strong evidence of diversification economies amongst most crop enterpr...

Journal: :Proceedings. Biological sciences 2008
Daniel L Rabosky Irby J Lovette

Evidence from both molecular phylogenies and the fossil record suggests that rates of species diversification often decline through time during evolutionary radiations. One proposed explanation for this pattern is ecological opportunity, whereby an initial abundance of resources and lack of potential competitors facilitate rapid diversification. This model predicts density-dependent declines in...

2016
Eric Lewitus Hélène Morlon

Identifying modes of species diversification is fundamental to our understanding of how biodiversity changes over evolutionary time. Diversification modes are captured in species phylogenies, but characterizing the landscape of diversification has been limited by the analytical tools available for directly comparing phylogenetic trees of groups of organisms. Here, we use a novel, non-parametric...

Journal: :Ecology letters 2008
Roland Jansson T Jonathan Davies

We used the largest DNA-based phylogeny of flowering plants to date to evaluate the importance of energy vs. past climate change in predicting global patterns in diversification. Relative diversification rates increased towards the equator, suggesting that differences in per-lineage net diversification may be an important component of the latitudinal diversity gradient. The amplitude of Quatern...

Journal: :Evolution; international journal of organic evolution 2012
Hélène Morlon Brian D Kemps Joshua B Plotkin Dustin Brisson

The current diversity of life on earth is the product of macroevolutionary processes that have shaped the dynamics of diversification. Although the tempo of diversification has been studied extensively in macroorganisms, much less is known about the rates of diversification in the exceedingly diverse and species-rich microbiota. Decreases in diversification rates over time, a signature of explo...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید