functional evolution
Dotaz
Zobrazit nápovědu
1st ed. iv, 360 s.
... Structure and Function of Biological Macromolecules 11 -- 2.1. The Nucleic Acids 13 -- 2.2. ... ... PRINCIPLES OF MOLECULAR SELECTION AND EVOLUTION -- 4. ... ... The Quality Function -- 7.2. Conditions for Stable Selection -- 7.3. ... ... Evolution in the Test-Tube 257 -- 13.1. The Qp Replicase System 258 -- 13.2. ... ... Experimental Perspectives: An Evolution Machine 272 -- 14. ...
ix, 321 s. : il., tab., grafy ; 26 cm
Diskuse o evoluci a povaze náboženství se podobá debatám o evoluci a povaze jazyka a hudby. Teorie, podle níž je náboženství vedlejším výtvorem evoluce, má za to, že jádrem náboženství je kontraintuitivní víra v nadpřirozené činitele. Ti jsou z valné části vytvářeni vrozenými „intuicemi“ týkajícími se schopnosti jednat, neboli „agency“. V náboženství lze rozlišit tři kognitivní složky: náboženské a další nadpřirozené reprezentace jsou kontraintuitivní, náboženství pomáhá zvládat úzkost (stejně jako ji dovede vytvářet), kromě toho je součástí náboženství množina chování, které se odchyluje od maximalizace užitku. Podle teorie, která chápe náboženství jako adaptaci, aniž by popírala argumentaci předešlých úvah, je základním přínosem náboženství posílení vnitroskupinové solidarity, a tím posílení zdatnosti člena skupiny. Kontraintuitivní víra nemusí podle této teorie být nutně maladaptivní. Soudobé funkční metody umožňují sledovat neuronální koreláty náboženské víry i mystické zkušenosti.
The discourse on evolution and the nature of religion is similar to discourse on evolution and nature of language and music. The first theory explaining religion as a by-product of evolution supposes that at the core of a religion is a contra-intuitive belief in supernatural agents arising from innate „intuitions“, related to agency. Three cognitive constituents can be recognised in religions: religious and other supernatural representations are contra-intuitive, religion helps with anxiety (but can also provoke anxiety) and a part of religion is behaviour that deviates from maximalization of benefit. The second theory, which perceives religion as an adaptation, does not dispute the aforementioned arguments but alleges that a basic benefit of religion is the reinforcement of intragroup solidarity and thereby fitness of a member of the group. Contra-intuitive belief does not need to be necessarily maladaptive. Contemporary functional methods make it possible to observe neural correlates of religious belief and mystical experiences.
Animals sense light primarily by an opsin-based photopigment present in a photoreceptor cell. Cnidaria are arguably the most basal phylum containing a well-developed visual system. The evolutionary history of opsins in the animal kingdom has not yet been resolved. Here, we study the evolution of animal opsins by genome-wide analysis of the cubozoan jellyfish Tripedalia cystophora, a cnidarian possessing complex lens-containing eyes and minor photoreceptors. A large number of opsin genes with distinct tissue- and stage-specific expression were identified. Our phylogenetic analysis unequivocally classifies cubozoan opsins as a sister group to c-opsins and documents lineage-specific expansion of the opsin gene repertoire in the cubozoan genome. Functional analyses provided evidence for the use of the Gs-cAMP signaling pathway in a small set of cubozoan opsins, indicating the possibility that the majority of other cubozoan opsins signal via distinct pathways. Additionally, these tests uncovered subtle differences among individual opsins, suggesting possible fine-tuning for specific photoreceptor tasks. Based on phylogenetic, expression and biochemical analysis we propose that rapid lineage- and species-specific duplications of the intron-less opsin genes and their subsequent functional diversification promoted evolution of a large repertoire of both visual and extraocular photoreceptors in cubozoans.
- MeSH
- AMP cyklický metabolismus MeSH
- biologická evoluce * MeSH
- Cubozoa genetika metabolismus MeSH
- exprese genu MeSH
- fotoreceptory metabolismus MeSH
- fylogeneze MeSH
- genom * MeSH
- genomika metody MeSH
- mapování chromozomů MeSH
- messenger RNA genetika MeSH
- multigenová rodina MeSH
- opsiny genetika metabolismus MeSH
- proteiny vázající GTP metabolismus MeSH
- signální transdukce MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
"Darwinova teorie" je nepřesný pojem. Ve skutečnosti existuje pět základních teorií, jimiž Darwin evoluci vysvětloval. Kromě doslovné víry v Bibli přijetí Darwinovy teorie bránily a brání esencialismus a finalismus. Esencialismus je podkladem transmutacionismu a transformacionismu, překonaných teorií. Darwin nahradil esencialismus populačním myšlením. V průběhu první poloviny minulého století vznikla Moderní syntéza evoluční teorie – neodarwinismus. Současná evoluční genomika potvrdila tři ze šesti pilířů Moderní syntézy: - náhodné dědičné variace jako materiální podklad evoluce, - totožnost základních evolučních procesů v průběhu celé evoluce, a - posledního univerzálního společného předka. Zamítla však další tři: - přírodní výběr jako dominantní hnací sílu evoluce, - gradualismus, čili průběh evoluce v nepatrných krůčcích, a - jednoduchou původní představu stromu života.
"Darwin's theory" is an inaccurate term. In reality there are five basic Darwinian theories of evolution. In addition to rejecting biblical literalism Darwin's theories impeded and impede essentialism and finalism. Essentialism is a basis of transmutationism and transformationism, both antiquated theories. Darwin replaced essentialism by population thinking. So-called Modern synthesis (neo-Darwinism) evolved in the first half of the last century. Contemporary evolutionary genomics corroborates three of the six pillars of Modern synthesis: - random heritable variations, - uniformitarianism and - the last universal common ancestor, but refutes the next three pillars: natural selection as the main driving force of evolution, gradualism (evolution in „infinitesimally“ small steps), and a single large Tree of life.
- Klíčová slova
- současná evoluční genomika, šest teoretických pilířů moderní syntézy (neodarwinismus), Darwinových pět teorií,
- MeSH
- biologická evoluce MeSH
- genomika MeSH
- Publikační typ
- úvodníky MeSH
Transposable elements (TEs) are able to jump to new locations (transposition) in the genome, usually after replication. They constitute the so-called selfish or junk DNA and take over large proportions of some genomes. Due to their ability to move around they can change the DNA landscape of genomes and are therefore a rich source of innovation in genes and gene regulation. Surge of sequence data in the past years has significantly facilitated large scale comparative studies. Cephalochordates have been regarded as a useful proxy to ancestral chordate condition partially due to the comparatively slow evolutionary rate at morphological and genomic level. In this study, we used opsin gene family from three Branchiostoma species as a window into cephalochordate genome evolution. We compared opsin complements in terms of family size, gene structure and sequence allowing us to identify gene duplication and gene loss events. Furthermore, analysis of the opsin containing genomic loci showed that they are populated by TEs. In summary, we provide evidence of the way transposable elements may have contributed to the evolution of opsin gene family and to the shaping of cephalochordate genomes in general.
BACKGROUND: Termites primarily feed on lignocellulose or soil in association with specific gut microbes. The functioning of the termite gut microbiota is partly understood in a handful of wood-feeding pest species but remains largely unknown in other taxa. We intend to fill this gap and provide a global understanding of the functional evolution of termite gut microbiota. RESULTS: We sequenced the gut metagenomes of 145 samples representative of the termite diversity. We show that the prokaryotic fraction of the gut microbiota of all termites possesses similar genes for carbohydrate and nitrogen metabolisms, in proportions varying with termite phylogenetic position and diet. The presence of a conserved set of gut prokaryotic genes implies that essential nutritional functions were present in the ancestor of modern termites. Furthermore, the abundance of these genes largely correlated with the host phylogeny. Finally, we found that the adaptation to a diet of soil by some termite lineages was accompanied by a change in the stoichiometry of genes involved in important nutritional functions rather than by the acquisition of new genes and pathways. CONCLUSIONS: Our results reveal that the composition and function of termite gut prokaryotic communities have been remarkably conserved since termites first appeared ~ 150 million years ago. Therefore, the "world's smallest bioreactor" has been operating as a multipartite symbiosis composed of termites, archaea, bacteria, and cellulolytic flagellates since its inception. Video Abstract.
- MeSH
- fylogeneze MeSH
- Isoptera * MeSH
- metagenom MeSH
- půda MeSH
- střevní mikroflóra * genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- audiovizuální média MeSH
- časopisecké články MeSH
- práce podpořená grantem MeSH
This paper examines telomeres from an evolutionary perspective. In the monocot plant order Asparagales two evolutionary switch-points in telomere sequence are known. The first occurred when the Arabidopsis-type telomere was replaced by a telomere based on a repeat motif more typical of vertebrates. The replacement is associated with telomerase activity, but the telomerase has low fidelity and this may have implications for the binding of telomeric proteins. At the second evolutionary switch-point, the telomere and its mode of synthesis are replaced by an unknown mechanism. Elsewhere in plants (Sessia, Vestia, Cestrum) and in arthropods, the telomere "typical" of the group is lost. Probably many other groups with "unusual" telomeres will be found. We question whether telomerase is indeed the original end-maintenance system and point to other candidate processes involving t-loops, t-circles, rolling circle replication and recombination. Possible evolutionary outcomes arising from the loss of telomerase activity in alternative lengthening of telomere (ALT) systems are discussed. We propose that elongation of minisatellite repeats using recombination/replication processes initially substitutes for the loss of telomerase function. Then in more established ALT groups, subtelomeric satellite repeats may replace the telomeric minisatellite repeat whilst maintaining the recombination/replication mechanisms for telomere elongation. Thereafter a retrotransposition-based end-maintenance system may become established. The influence of changing sequence motifs on the properties of the telomere cap is discussed. The DNA and protein components of telomeres should be regarded--as with any other chromosome elements--as evolving and co-evolving over time and responding to changes in the genome and to environmental stresses. We describe how telomere dysfunction, resulting in end-to-end chromosome fusions, can have a profound effect on chromosome evolution and perhaps even speciation.
