scholarly journals Introduction

2002 ◽  
Vol 357 (1419) ◽  
pp. 237-240 ◽  
Author(s):  
S. Balshine ◽  
B. Kempenaers ◽  
T. Székely
Keyword(s):  
Parental Care ◽  
Life History Traits ◽  
Genetic Relatedness ◽  
Early Stage ◽  
State Dependence ◽  
Theoretical Models ◽  
Feedback Loops ◽  
Likelihood Methods ◽  
Phylogenetic Reconstructions ◽  
Maximum Likelihood Methods

In the last decade, studies of parental care have rapidly proliferated. This increased interest in parental care has been stimulated by advances in three fields. First, the revolution in molecular biology has generated techniques that are increasingly used by behavioural scientists. Such techniques include DNA fingerprinting, which allows researchers to identify the genetic relatedness between putative parents and offspring, and molecular sex markers that allow researchers to determine the sex of offspring at an early stage before external differences have developed. In addition, gene sequencing, which is now fast and relatively inexpensive, has generated vast quantities of data, which are increasingly used to reveal evolutionary relationships that complement older morphology–based phylogenies. This has led to the second advance: several novel statistical techniques, which include parsimony and maximum–likelihood methods for phylogenetic reconstructions, have been developed to investigate past evolutionary events. These techniques provide new opportunities to examine the origins of parental care behaviour, the direction of parental care evolution and life history traits that may have influenced parental care evolution. Third, mathematical modelling of parental care has matured and now encompasses a range of game–theoretical models, some of which take account of state dependence and stochasticity. There has also been an effort to consider the feedback loops between parenting decisions and mating decisions. Some of these models were motivated by the growing consensus that parental care is one of the main battlefields for conflict between the sexes. New mathematical models have been essential in understanding aspects of these conflicts.

Systematics of Capparaceae and Cleomaceae: an evaluation of the generic delimitations of Capparis and Cleome using plastid DNA sequence dataThis paper is one of a selection of papers published in the Special Issue on Systematics Research.

Botany ◽  
2008 ◽  
Vol 86 (7) ◽  
pp. 682-696 ◽  
Author(s):  
Jocelyn C. Hall
Keyword(s):  
Geographic Distribution ◽  
New World ◽  
Plastid Dna ◽  
Likelihood Methods ◽  
Phylogenetic Reconstructions ◽  
The Family ◽  
Maximum Likelihood Methods ◽  
Taxonomic Implications ◽  
Cleome Arabica ◽  
Selection Of

The phylogenetic relationships in Capparaceae and Cleomaceae were examined using two plastid genes, ndhF and matK, to address outstanding systematic questions in the two families. Specifically, the monophyly of the two type genera, Capparis and Cleome , has recently been questioned. Capparaceae and Cleomaceae were broadly sampled to assess the generic circumscriptions of both genera, which house the majority of species for each family. Phylogenetic reconstructions using maximum parsimony and maximum likelihood methods strongly contradict monophyly for both type genera. Within Capparaceae, Capparis is diphyletic: the sampled species belong to two of the five major lineages recovered in the family, which corresponds with their geographic distribution. One lineage contains all sampled New World Capparis and four other genera ( Atamisquea , Belencita , Morisonia , and Steriphoma ) that are distributed exclusively in the New World. The other lineage contains Capparis species from the Old World and Australasia, as well as the Australian genus, Apophyllum . Species of Cleome are scattered across each of four major lineages identified within Cleomaceae: (i) Cleome in part, Dactylaena , Dipterygium , Gynandropsis , Podandrogyne , and Polanisia ; (ii) Cleome droserifolia (Forssk.) Del.; (iii)  Cleome arabica L., and Cleome ornithopodioides L.; and (iv) Cleome in part, Cleomella , Isomeris , Oxystylis , and Wislizenia . Resolution within and among these major clades of Cleomaceae is limited, and there is no clear correspondence of clades with geographic distribution. Within each family, morphological support and taxonomic implications of the molecular-based clades are discussed.

scholarly journals The evolution of parental care and egg size: a comparative analysis in frogs

2005 ◽  
Vol 273 (1587) ◽  
pp. 687-692 ◽  
Author(s):  
Kyle Summers ◽  
Christian Sea McKeon ◽  
Heather Heying
Keyword(s):  
Parental Care ◽  
Egg Size ◽  
Scientific Literature ◽  
Matrix Representation ◽  
Phylogenetic Analyses ◽  
Likelihood Methods ◽  
Evolutionary Transitions ◽  
Size Evolution ◽  
Maximum Likelihood Methods ◽  
Context Data

The evolution of parental care and egg size has attracted considerable attention and theoretical debate. Several different hypotheses have been proposed concerning the trajectories of parental care and egg size evolution and the order of specific evolutionary transitions. Few comparative studies have investigated the predictions of these hypotheses. Here, we investigate the evolutionary association between parental care and egg size in frogs in a phylogenetic context. Data on egg size and presence or absence of parental care in various species of frogs was gathered from the scientific literature. As a basis for our comparative analyses, we developed a phylogenetic supertree, by combining the results of multiple phylogenetic analyses in the literature using matrix representation parsimony. Using phylogenetic pairwise comparisons we demonstrated a significant association between the evolution of parental care and large egg size. We then used recently developed maximum likelihood methods to infer the evolutionary order of specific transitions. This analysis revealed that the evolution of large egg size typically precedes the evolution of parental care, rather than the reverse. We discuss the relevance of our results to previous hypotheses concerning the evolution of parental care and egg size.

scholarly journals Selecting between causal and noncausal models with quantile autoregressions

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Alain Hecq ◽  
Li Sun
Keyword(s):  
Time Series ◽  
Maximum Likelihood ◽  
Latin American ◽  
Financial Time Series ◽  
Selection Criterion ◽  
Likelihood Methods ◽  
Approximate Maximum Likelihood ◽  
Financial Time ◽  
Maximum Likelihood Methods ◽  
Latin American Countries

AbstractWe propose a model selection criterion to detect purely causal from purely noncausal models in the framework of quantile autoregressions (QAR). We also present asymptotics for the i.i.d. case with regularly varying distributed innovations in QAR. This new modelling perspective is appealing for investigating the presence of bubbles in economic and financial time series, and is an alternative to approximate maximum likelihood methods. We illustrate our analysis using hyperinflation episodes of Latin American countries.

scholarly journals A Generalized Rayleigh Family of Distributions Based on the Modified Slash Model

Symmetry ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1226
Author(s):  
Inmaculada Barranco-Chamorro ◽  
Yuri A. Iriarte ◽  
Yolanda M. Gómez ◽  
Juan M. Astorga ◽  
Héctor W. Gómez
Keyword(s):  
Heavy Tails ◽  
Real Data ◽  
Rate Function ◽  
Data Sets ◽  
Estimation Of Parameters ◽  
Stochastic Representation ◽  
Likelihood Methods ◽  
Chi Square ◽  
Maximum Likelihood Methods ◽  
Family Of Distributions

Specifying a proper statistical model to represent asymmetric lifetime data with high kurtosis is an open problem. In this paper, the three-parameter, modified, slashed, generalized Rayleigh family of distributions is proposed. Its structural properties are studied: stochastic representation, probability density function, hazard rate function, moments and estimation of parameters via maximum likelihood methods. As merits of our proposal, we highlight as particular cases a plethora of lifetime models, such as Rayleigh, Maxwell, half-normal and chi-square, among others, which are able to accommodate heavy tails. A simulation study and applications to real data sets are included to illustrate the use of our results.

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