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1.
Adv Exp Med Biol ; 1175: 15-44, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31583583

RESUMO

As the nervous system evolved from the diffused to centralised form, the neurones were joined by the appearance of the supportive cells, the neuroglia. Arguably, these non-neuronal cells evolve into a more diversified cell family than the neurones are. The first ancestral neuroglia appeared in flatworms being mesenchymal in origin. In the nematode C. elegans proto-astrocytes/supportive glia of ectodermal origin emerged, albeit the ensheathment of axons by glial cells occurred later in prawns. The multilayered myelin occurred by convergent evolution of oligodendrocytes and Schwann cells in vertebrates above the jawless fishes. Nutritive partitioning of the brain from the rest of the body appeared in insects when the hemolymph-brain barrier, a predecessor of the blood-brain barrier was formed. The defensive cellular mechanism required specialisation of bona fide immune cells, microglia, a process that occurred in the nervous system of leeches, bivalves, snails, insects and above. In ascending phylogeny, new type of glial cells, such as scaffolding radial glia, appeared and as the bran sizes enlarged, the glia to neurone ratio increased. Humans possess some unique glial cells not seen in other animals.


Assuntos
Evolução Biológica , Neuroglia/citologia , Animais , Caenorhabditis elegans , Humanos , Bainha de Mielina , Neurônios/citologia , Oligodendroglia/citologia
2.
Science ; 365(6457): 981-982, 2019 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-31488673
3.
Adv Exp Med Biol ; 1159: 5-31, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31502197

RESUMO

Mitochondria and bacteria share a myriad of properties since it is believed that the powerhouses of the eukaryotic cell have evolved from a prokaryotic origin. Ribosomal RNA sequences, DNA architecture and metabolism are strikingly similar in these two entities. Proteins and nucleic acids have been a hallmark for comparison between mitochondria and prokaryotes. In this chapter, similarities (and differences) between mitochondrial and prokaryotic membranes are addressed with a focus on structure-function relationship of different lipid classes. In order to be suitable for the theme of the book, a special emphasis is reserved to the effects of bioactive sphingolipids, mainly ceramide, on mitochondrial membranes and their roles in initiating programmed cell death.


Assuntos
Evolução Biológica , Membrana Celular/química , Lipídeos/química , Mitocôndrias/química , Células Procarióticas/química , Ceramidas , Esfingolipídeos
4.
Behav Brain Sci ; 42: e122, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31407975

RESUMO

A collective action problem exists not only in offensive warfare, but also in defensive situations. The collective action problem is dealt with in the same way in offensive and defensive warfare: by strong leadership, discipline, rewards and punishments, strong group identification, strict religiosity, and intolerance of deviants. This behavior is explained in terms of evolutionary psychology.


Assuntos
Evolução Biológica , Guerra
5.
Behav Brain Sci ; 42: e134, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31407980

RESUMO

Many modern-day groups differ from prehistoric ones regarding the proportion of members who are related to any particular individual. From an evolutionary mismatch lens, an appreciation of this disparity could help better explain the potential dilution of group cohesion during peacetime and inform novel, more effective approaches to enhancing group unity - strategies that might enhance national security around the globe.


Assuntos
Processos Grupais , Relações Interpessoais , Evolução Biológica
6.
Behav Brain Sci ; 42: e137, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31407982

RESUMO

Attempts to understand the fundamental forces shaping conflict between attacking and defending groups can be hampered by a narrow focus on humans and reductionist, oversimplified modelling. Further progress depends on recognising the striking parallels in between-group conflict across the animal kingdom, harnessing the power of experimental tests in nonhuman species and modelling the eco-evolutionary feedbacks that drive attack and defence.


Assuntos
Evolução Biológica , Ecologia , Animais
7.
Behav Brain Sci ; 42: e145, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31407991

RESUMO

Our target article modeled conflict within and between groups as an asymmetric game of strategy and developed a framework to explain the evolved neurobiological, psychological, and sociocultural mechanisms underlying attack and defense. Twenty-seven commentaries add insights from diverse disciplines, such as animal biology, evolutionary game theory, human neuroscience, psychology, anthropology, and political science, that collectively extend and supplement this model in three ways. Here we draw attention to the superordinate structure of attack and defense, and its subordinate means to meet the end of status quo maintenance versus change, and we discuss (1) how variations in conflict structure and power disparities between antagonists can impact strategy selection and behavior during attack and defense; (2) how the positions of attack and defense emerge endogenously and are subject to rhetoric and propaganda; and (3) how psychological and economic interventions can transform attacker-defender conflicts into coordination games that allow mutual gains and dispute resolution.


Assuntos
Evolução Biológica , Teoria do Jogo , Animais , Humanos
8.
An Acad Bras Cienc ; 91(suppl 3): e20190218, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31411243

RESUMO

Amazonia has been a focus of interest since the early days of biogeography as an intrinsically complex and extremely diverse region. This region comprises an intricate mosaic that includes diverse types of forest formations, flooded environments and open vegetation. Increased knowledge about the distribution of species in Amazonia has led to the recognition of complex biogeographic patterns. The confrontation of these biogeographic patterns with information on the geological and climatic history of the region has generated several hypotheses dedicated to explain the origin of the biological diversity. Genomic information, coupled with knowledge of Earth's history, especially the evolution of the Amazonian landscape, presents fascinating possibilities for understanding the mechanisms that govern the origin and maintenance of diversity patterns in one of the most diverse regions of the world. For this we will increasingly need more intense and coordinated interactions between researchers studying biotic diversification and the evolution of landscapes. From the interaction between these two fields of knowledge that are in full development, an increasingly detailed understanding of the historical mechanisms related to the origin of the species will surely arise.


Assuntos
Biodiversidade , Evolução Biológica , Aves/classificação , Filogeografia , Animais , Brasil , Ecossistema
9.
An Acad Bras Cienc ; 91(suppl 2): e20180614, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31411248

RESUMO

Discoveries in Carnian-aged rocks are establishing a rich and diverse dinosaurian fauna at the so-called 'dawn of the age of dinosaurs' in the Late Triassic of Western Gondwana. Accordingly, Brazilian strata from the Candelária Sequence have contributed extensively to this trend. Here, we present a new dinosaurian specimen (CAPPA/UFSM 0200) from this geological unit. The material was collected at a fossiliferous site that had no previous record of dinosaurs. Our specimen comprises a single ilium, which we describe in detail. Its anatomy is consistent with Carnian sauropodomorph dinosaurs, but differs from coeval specimens by several features, although we do not discard the possibility of these features being the result of intraspecific variation. In part of our phylogenetic investigation, CAPPA/UFSM 0200 was recovered within Saturnaliinae, a group comprised of Carnian sauropodomorphs from South America. However, based on examination of better-sampled coeval taxa, a character (a strong rugosity in the ilium) supporting this less inclusive position might be related to intraspecific variation and so, should be carefully considered. This study increases the distribution of dinosaur remains in fossiliferous units from southern Brazil and adds to the discussion regarding intraspecific variation and its implications in the phylogeny of early dinosaurs.


Assuntos
Dinossauros/anatomia & histologia , Ílio/anatomia & histologia , Animais , Evolução Biológica , Brasil , Dinossauros/classificação , Filogenia , Especificidade da Espécie
10.
J Agric Food Chem ; 67(35): 9950-9957, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31403788

RESUMO

Protein glycosylation is a ubiquitous posttranslational modification that modulates protein properties, thereby influencing bioactivities within a system. Duck egg white (DEW) proteins exhibit diverse biological properties compared with their chicken egg white (CEW) counterparts, which might be related to glycosylation. N-Glycoproteome analysis of DEW was conducted, and a total of 231 N-glycosites from 68 N-glycoproteins were identified. Gene ontology analysis was used to elucidate the biofunctions of DEW N-glycoproteins and compare them with those of CEW, which showed that the differences mostly involved molecular functions and biological processes. The biological functions of DEW N-glycoproteins were illuminated through bioinformatics analysis and comparison with CEW orthologues, which showed different allergenicities and antibacterial abilities. These divergences might be initiated by specific alterations in glycosylation, which can enhance the proteolysis resistance and protein steric hindrance. These results provide new insights for discovering the effects of N-glycosylation on biofunctions during the divergence of homologous proteins.


Assuntos
Galinhas/genética , Patos/genética , Proteínas do Ovo/química , Glicoproteínas/química , Animais , Evolução Biológica , Galinhas/metabolismo , Patos/metabolismo , Proteínas do Ovo/genética , Proteínas do Ovo/metabolismo , Clara de Ovo/química , Glicoproteínas/genética , Glicoproteínas/metabolismo , Glicosilação , Proteômica
11.
BMC Bioinformatics ; 20(1): 420, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31409290

RESUMO

BACKGROUND: Lineage rate heterogeneity can be a major source of bias, especially in multi-gene phylogeny inference. We had previously tackled this issue by developing LS3, a data subselection algorithm that, by removing fast-evolving sequences in a gene-specific manner, identifies subsets of sequences that evolve at a relatively homogeneous rate. However, this algorithm had two major shortcomings: (i) it was automated and published as a set of bash scripts, and hence was Linux-specific, and not user friendly, and (ii) it could result in very stringent sequence subselection when extremely slow-evolving sequences were present. RESULTS: We address these challenges and produce a new, platform-independent program, LSX, written in R, which includes a reprogrammed version of the original LS3 algorithm and has added features to make better lineage rate calculations. In addition, we developed and included an alternative version of the algorithm, LS4, which reduces lineage rate heterogeneity by detecting sequences that evolve too fast and sequences that evolve too slow, resulting in less stringent data subselection when extremely slow-evolving sequences are present. The efficiency of LSX and of LS4 with datasets with extremely slow-evolving sequences is demonstrated with simulated data, and by the resolution of a contentious node in the catfish phylogeny that was affected by an unusually high lineage rate heterogeneity in the dataset. CONCLUSIONS: LSX is a new bioinformatic tool, with an accessible code, and with which the effect of lineage rate heterogeneity can be explored in gene sequence datasets of virtually any size. In addition, the two modalities of the sequence subsampling algorithm included, LS3 and LS4, allow the user to optimize the amount of non-phylogenetic signal removed while keeping a maximum of phylogenetic signal.


Assuntos
Evolução Biológica , Evolução Molecular , Software , Algoritmos , Biologia Computacional/métodos , Filogenia
12.
Genome Biol ; 20(1): 136, 2019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300020

RESUMO

BACKGROUND: Bread wheat is one of the most important and broadly studied crops. However, due to the complexity of its genome and incomplete genome collection of wild populations, the bread wheat genome landscape and domestication history remain elusive. RESULTS: By investigating the whole-genome resequencing data of 93 accessions from worldwide populations of bread wheat and its diploid and tetraploid progenitors, together with 90 published exome-capture data, we find that the B subgenome has more variations than A and D subgenomes, including SNPs and deletions. Population genetics analyses support a monophyletic origin of domesticated wheat from wild emmer in northern Levant, with substantial introgressed genomic fragments from southern Levant. Southern Levant contributes more than 676 Mb in AB subgenomes and enriched in the pericentromeric regions. The AB subgenome introgression happens at the early stage of wheat speciation and partially contributes to their greater genetic diversity. Furthermore, we detect massive alien introgressions that originated from distant species through natural and artificial hybridizations, resulting in the reintroduction of ~ 709 Mb and ~ 1577 Mb sequences into bread wheat landraces and varieties, respectively. A large fraction of these intra- and inter-introgression fragments are associated with quantitative trait loci of important traits, and selection events are also identified. CONCLUSION: We reveal the significance of multiple introgressions from distant wild populations and alien species in shaping the genetic components of bread wheat, and provide important resources and new perspectives for future wheat breeding.


Assuntos
Evolução Biológica , Variação Genética , Genoma de Planta , Hibridização Genética , Triticum/genética , Cromossomos de Plantas , Domesticação , Sequenciamento Completo do Genoma
13.
Genome Biol ; 20(1): 139, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31307500

RESUMO

BACKGROUND: Bread wheat is an allohexaploid species with a 16-Gb genome that has large intergenic regions, which presents a big challenge for pinpointing regulatory elements and further revealing the transcriptional regulatory mechanisms. Chromatin profiling to characterize the combinatorial patterns of chromatin signatures is a powerful means to detect functional elements and clarify regulatory activities in human studies. RESULTS: In the present study, through comprehensive analyses of the open chromatin, DNA methylome, seven major chromatin marks, and transcriptomic data generated for seedlings of allohexaploid wheat, we detected distinct chromatin architectural features surrounding various functional elements, including genes, promoters, enhancer-like elements, and transposons. Thousands of new genic regions and cis-regulatory elements are identified based on the combinatorial pattern of chromatin features. Roughly 1.5% of the genome encodes a subset of active regulatory elements, including promoters and enhancer-like elements, which are characterized by a high degree of chromatin openness and histone acetylation, an abundance of CpG islands, and low DNA methylation levels. A comparison across sub-genomes reveals that evolutionary selection on gene regulation is targeted at the sequence and chromatin feature levels. The divergent enrichment of cis-elements between enhancer-like sequences and promoters implies these functional elements are targeted by different transcription factors. CONCLUSIONS: We herein present a systematic epigenomic map for the annotation of cis-regulatory elements in the bread wheat genome, which provides new insights into the connections between chromatin modifications and cis-regulatory activities in allohexaploid wheat.


Assuntos
Montagem e Desmontagem da Cromatina , Metilação de DNA , Código das Histonas , Elementos Reguladores de Transcrição , Triticum/genética , Evolução Biológica , Epigenômica , Genoma de Planta , Plântula/metabolismo , Triticum/metabolismo
14.
Nat Commun ; 10(1): 2916, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31266954

RESUMO

Sterols and hopanoids are chemically and structurally related lipids mostly found in eukaryotic and bacterial cell membranes. Few bacterial species have been reported to produce sterols and this anomaly had originally been ascribed to lateral gene transfer (LGT) from eukaryotes. In addition, the functions of sterols in these bacteria are unknown and the functional overlap between sterols and hopanoids is still unclear. Gemmata obscuriglobus is a bacterium from the Planctomycetes phylum that synthesizes sterols, in contrast to its hopanoid-producing relatives. Here we show that sterols are essential for growth of G. obscuriglobus, and that sterol depletion leads to aberrant membrane structures and defects in budding cell division. This report of sterol essentiality in a prokaryotic species advances our understanding of sterol distribution and function, and provides a foundation to pursue fundamental questions in evolutionary cell biology.


Assuntos
Proteínas de Bactérias/genética , Planctomycetales/metabolismo , Esteróis/biossíntese , Proteínas de Bactérias/metabolismo , Evolução Biológica , Planctomycetales/genética , Planctomycetales/crescimento & desenvolvimento
15.
An Acad Bras Cienc ; 91(suppl 2): e20180374, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31340217

RESUMO

In the last two decades, the number of phylogenetically informative anatomical characters recognized in the appendicular skeleton of titanosaurian sauropod dinosaurs has increased dramatically with the discovery of new and comparatively complete specimens. Here we provide an overview of the appendicular skeletal morphology of South American titanosaurs and discuss its significance for phylogenetic reconstruction. The appendicular skeletal diversity of South American titanosaurs is substantially greater than was initially appreciated. Moreover, some regions of the appendicular skeleton, such as the pes, exhibit remarkable variability in form. Multiple synapomorphies of Titanosauria and the less inclusive clades Lithostrotia and Saltasauridae consist of characters of the girdles and limbs. Although the phylogenetic definitions of titanosaurian clades such as Saltasaurinae and Lognkosauria are stable, the taxonomic content of these clades has varied in recent analyses depending on the phylogenetic topology recovered. Within Titanosauria, the results of four recent, largely independent analyses support the existence of a derived titanosaurian lineage distinct from the 'Saltasaurinae line,' which is herein termed Colossosauria. At present, this clade is mainly comprised by taxa within Lognkosauria and Rinconsauria, and is useful in discussions of titanosaurian lower-level relationships.


Assuntos
Dinossauros/anatomia & histologia , Fósseis/anatomia & histologia , Animais , Evolução Biológica , Dinossauros/classificação , Osteologia , Filogenia , América do Sul
16.
Brain Nerve ; 71(7): 807-813, 2019 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-31289254

RESUMO

Cognitive abilities of humans are superior to that of non-human primates (NHP). Differences in genes, gene expression, cellular composition and response, neural circuit, and brain volume between humans and NHP underlying cognitive abilities are discussed, with a focus on cortical expansion, prefrontal expansion, language-related areas, and the adaptation of longer life spans in humans.


Assuntos
Evolução Biológica , Encéfalo/fisiologia , Córtex Pré-Frontal/fisiologia , Especificidade da Espécie , Animais , Humanos , Primatas
17.
Ecol Lett ; 22(10): 1620-1628, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31353805

RESUMO

Although mothers influence the traits of their offspring in many ways beyond the transmission of genes, it remains unclear how important such 'maternal effects' are to phenotypic differences among individuals. Synthesizing estimates derived from detailed pedigrees, we evaluated the amount of phenotypic variation determined by maternal effects in animal populations. Maternal effects account for half as much phenotypic variation within populations as do additive genetic effects. Maternal effects most greatly affect morphology and phenology but, surprisingly, are not stronger in species with prolonged maternal care than in species without. While maternal effects influence juvenile traits more than adult traits on average, they do not decline across ontogeny for behaviour or physiology, and they do not weaken across the life cycle in species without maternal care. These findings underscore maternal effects as an important source of phenotypic variation and emphasise their potential to affect many ecological and evolutionary processes.


Assuntos
Genética Populacional , Herança Materna , Animais , Evolução Biológica , Ecologia , Feminino , Fenótipo
18.
Nature ; 571(7766): 500-504, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31292546

RESUMO

Two fossilized human crania (Apidima 1 and Apidima 2) from Apidima Cave, southern Greece, were discovered in the late 1970s but have remained enigmatic owing to their incomplete nature, taphonomic distortion and lack of archaeological context and chronology. Here we virtually reconstruct both crania, provide detailed comparative descriptions and analyses, and date them using U-series radiometric methods. Apidima 2 dates to more than 170 thousand years ago and has a Neanderthal-like morphological pattern. By contrast, Apidima 1 dates to more than 210 thousand years ago and presents a mixture of modern human and primitive features. These results suggest that two late Middle Pleistocene human groups were present at this site-an early Homo sapiens population, followed by a Neanderthal population. Our findings support multiple dispersals of early modern humans out of Africa, and highlight the complex demographic processes that characterized Pleistocene human evolution and modern human presence in southeast Europe.


Assuntos
Cavernas , Fósseis , Crânio/anatomia & histologia , Animais , Evolução Biológica , Grécia , Humanos , Homem de Neandertal/anatomia & histologia , Homem de Neandertal/classificação , Análise de Componente Principal , Datação Radiométrica , Fatores de Tempo
19.
BMC Evol Biol ; 19(1): 147, 2019 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-31324139

RESUMO

BACKGROUND: For the understanding of human nature, the evolutionary roots of human moral behaviour are a key precondition. Our question is as follows: Can the altruistic moral rule "Risk your life to save your family members, if you want them to save your life" be evolutionary stable? There are three research approaches to investigate this problem: kin selection, group selection and population genetics modelling. The present study is strictly based on the last approach. RESULTS: We consider monogamous and exogamous families, where at an autosomal locus, dominant-recessive alleles determine the phenotypes in a sexual population. Since all individuals' survival rate is determined by their altruistic family members, we introduce a new population genetics model based on the mating table approach and adapt the verbal definition of evolutionary stability to genotypes. In general, when the resident is recessive, a homozygote is an evolutionarily stable genotype (ESG), if the number of survivors of the resident genotype of the resident homozygote family is greater than that of non-resident heterozygote survivors of the family of the resident homozygote and mutant heterozygote genotypes. Using the introduced genotype dynamics we proved that in the recessive case ESG implies local stability of the altruistic genotype. We apply our general ESG conditions for self-sacrificing life history strategy when the number of new-born offspring does not depend on interactions within the family and the interactions are additive. We find that in this case our ESG conditions give back Hamilton's rule for evolutionary stability of the self-sacrificing life history strategy. CONCLUSIONS: In spite of the fact that the kidney transplantations was not a selection factor during the earlier human evolution, nowadays "self-sacrificing" can be observed in the live donor kidney transplantations, when the donor is one of the family members. It seems that selection for self-sacrificing in family produced an innate moral tendency in modulating social cognition in human brain.


Assuntos
Evolução Biológica , Estágios do Ciclo de Vida , Comportamento Sexual , Animais , Genética Populacional , Genótipo , Humanos , Mutação/genética , Fenótipo
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