Evolutionary history of the arid climate‐adapted Helichrysum (Asteraceae: Gnaphalieae): Cape origin and association between annual life‐history and low chromosome numbers

2019 ◽  
Vol 57 (5) ◽  
pp. 468-487
Author(s):  
Santiago Andrés‐Sánchez ◽  
G. Anthony Verboom ◽  
Mercè Galbany‐Casals ◽  
Nicola G. Bergh
Keyword(s):  
Life History ◽  
Chromosome Numbers ◽  
Evolutionary History ◽  
Arid Climate ◽  
History Of ◽  
Annual Life History

Seasonal cycle of the nest composition in the Ponerine ant Cryptopone sauteri (Hymenoptera: Formicidae)

Sociobiology ◽  
2017 ◽  
Vol 64 (4) ◽  
pp. 393
Author(s):  
Yuki Yamaguchi ◽  
Hiromi Yazawa ◽  
Satoru Iwanishi ◽  
Kazuyuki Kudô
Keyword(s):  
Life History ◽  
Seasonal Changes ◽  
Seasonal Cycle ◽  
Quantitative Information ◽  
Social Structures ◽  
Ecological Studies ◽  
Brood Development ◽  
Ponerine Ant ◽  
History Of ◽  
Annual Life History

The annual life history is a basic and important factor in ecological studies on temperate ant species. The biology of Ponerinae species has been studied for many species, but little attention has been paid to their life history. Cryptopone sauteri is one of the most common ants in temperate regions of Japan. However, there is no quantitative information on the life history of this species. We report seasonal changes in brood development, the emergence of reproductives and social structures of C. sauteri. Additionally, we discuss that this species possibly exhibits a polydomous nesting system.

scholarly journals Evolution of morphological and climatic adaptations inVeronica L.(Plantaginaceae)

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2333 ◽  
Author(s):  
Jian-Cheng Wang ◽  
Bo-Rong Pan ◽  
Dirk C. Albach
Keyword(s):  
Life History ◽  
Substitution Rate ◽  
Parallel Evolution ◽  
Morphological Characters ◽  
Annual Species ◽  
Selective Pressures ◽  
History Of ◽  
Phylogenetic Perspective ◽  
Drought Resistant ◽  
Annual Life History

Perennials and annuals apply different strategies to adapt to the adverse environment, based on ‘tolerance’ and ‘avoidance’, respectively. To understand lifespan evolution and its impact on plant adaptability, we carried out a comparative study of perennials and annuals in the genusVeronicafrom a phylogenetic perspective. The results showed that ancestors of the genusVeronicawere likely to be perennial plants. Annual life history ofVeronicahas evolved multiple times and subtrees with more annual species have a higher substitution rate. Annuals can adapt to more xeric habitats than perennials. This indicates that annuals are more drought-resistant than their perennial relatives. Due to adaptation to similar selective pressures, parallel evolution occurs in morphological characters among annual species ofVeronica.

scholarly journals Coral symbiotic algae calcifyex hospitein partnership with bacteria

2015 ◽  
Vol 112 (19) ◽  
pp. 6158-6163 ◽  
Author(s):  
Jörg C. Frommlet ◽  
Maria L. Sousa ◽  
Artur Alves ◽  
Sandra I. Vieira ◽  
David J. Suggett ◽  
...  
Keyword(s):  
Life History ◽  
Coral Reef ◽  
Evolutionary History ◽  
Central Importance ◽  
Free Living ◽  
Algal Communities ◽  
Symbiotic Algae ◽  
Coral Reef Ecosystems ◽  
History Of

Dinoflagellates of the genusSymbiodiniumare commonly recognized as invertebrate endosymbionts that are of central importance for the functioning of coral reef ecosystems. However, the endosymbiotic phase withinSymbiodiniumlife history is inherently tied to a more cryptic free-living (ex hospite) phase that remains largely unexplored. Here we show that free-livingSymbiodiniumspp. in culture commonly form calcifying bacterial–algal communities that produce aragonitic spherulites and encase the dinoflagellates as endolithic cells. This process is driven bySymbiodiniumphotosynthesis but occurs only in partnership with bacteria. Our findings not only place dinoflagellates on the map of microbial–algal organomineralization processes but also point toward an endolithic phase in theSymbiodiniumlife history, a phenomenon that may provide new perspectives on the biology and ecology ofSymbiodiniumspp. and the evolutionary history of the coral–dinoflagellate symbiosis.

scholarly journals The chromosome cycle in Coccidia and Gregarines

1915 ◽  
Vol 89 (610) ◽  
pp. 83-94 ◽  
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Chromosome Numbers ◽  
Life Histories ◽  
The Other ◽  
Chromosome Cycle ◽  
History Of ◽  
Careful Investigation

Despite the large amount of work which has already been devoted to the study of the Coccidia and Gregarines, very little indeed is known definitely about the behaviour of the chromosomes in these Protozoa. Not only has the chromosome cycle been left uninvestigated and undescribed in the majority of these organisms which have hitherto been studied, but the very existence of chromosomes in the nuclear divisions at many stages in the life-history of certain forms has even been denied; and the most contradictory and unsatis­factory accounts have been given of that most important phase in the life-cycle of the chromosomes—the phase of meiosis, or reduction. In order to fill up this gap in our knowledge of the Sporozoa, we have made —during the last few years—a very detailed study of the chromosomes of a coccidian and a gregarine. One of us (C. D.) has investigated the coccidian Aggregate eberthi Labbé, whilst the other (A. P. J.) has studied the gregarine Diplocystis schneideri Kunstler. Careful investigation of these two organisms has shown that the nuclear divisions at all stages in the life-histories are mitotic, and that the chromosome numbers are remarkably constant.

The function and evolution of penicillinase

1971 ◽  
Vol 179 (1057) ◽  
pp. 385-401 ◽  
Keyword(s):  
Life History ◽  
Chemical Structure ◽  
Evolutionary History ◽  
Physiological Function ◽  
Biochemical Evolution ◽  
Structural Genes ◽  
Ecological Relationships ◽  
History Of ◽  
Intimate Knowledge ◽  
Specific Inhibitors

In order to construct biologically useful hypotheses on plausible pathways for the evolution of an enzyme, it is important to know something about the probable physiological function, as well as the chemistry, of the molecular varieties existing at present. Yet, function of a part of an organism—be it a morphological entity or simply a species of protein—is a notoriously subjective quality, difficult to assess without intimate knowledge of the life history of the organism and its natural ecological relationships. Chemical structure, for these purposes, is equivalent to amino acid sequence, for it is by comparison of different sequences in a homologous series of proteins that some idea can be obtained as to the most likely steps in their biochemical evolution at the level of the structural genes concerned. In this critical review, it is argued that existing evidence on the whole tends to favour the conclusion that the β-lactamases function in general as detoxifying agents, acting against the penicillins and cephalosporins, and that their evolutionary history has been tuned by selection in a natural environment where these classes of compound have operated as specific inhibitors of bacterial growth.

scholarly journals Amniotic diversity of Taranga Hill-forest, Gujarat, India

Our Nature ◽  
1970 ◽  
Vol 8 (1) ◽  
pp. 144-156 ◽  
Author(s):  
C.D. Patel ◽  
M.I. Patel
Keyword(s):  
Evolutionary History ◽  
Food Sources ◽  
Arid Climate ◽  
Low Diversity ◽  
History Of ◽  
Semi Arid ◽  
High Diversity

Amniotes is the group of the animals’ viz., reptiles, birds and mammals, in which extra-embryonic membranes are developed around the embryo for different functions. Amniotic diversity of Taranga Hill-forest (THf) has been studied. THf was represented by 147 species belonging to 116 genera and 62 families. Of these, 24 species were reptiles (belonging 21 genus and 11 families), 98 species were birds (belonging 73 genus and 35 families) and 25 species were mammals (belonging 22 genus and 16 families). It shows that THf has good amniotic diversity. The THf covers 21.21% amniotic diversity of Gujarat and 7.07% of India. The total amniotic diversity of THf was covered by 66.67% species of birds, 17.01% species of mammals and 16.33% species of reptiles. Of the total 62 families, 6 families have high diversity, 18 families have moderate diversity, 10 families have low diversity and 28 families have very low diversity. The high-diversified six families were Colubridae, Accipitridae, Corvidae, Muscicapidae, Sylviidae and Passeridae. Diversity in an area is dependent upon the availability of variable food sources, habitats for roosting, resting, breeding and sheltering; semi-arid climate and evolutionary history of the Aravalli ranges.DOI: 10.3126/on.v8i1.4322

Gender dependent and independent morphological dimorphism in sexual and apomictic Antennaria monocephala sensu lato

1991 ◽  
Vol 69 (7) ◽  
pp. 1433-1448 ◽  
Author(s):  
J. G. Chmielewski ◽  
C. C. Chinnappa
Keyword(s):  
Chromosome Number ◽  
Key Words ◽  
Reproductive Biology ◽  
Chromosome Numbers ◽  
Evolutionary History ◽  
Multivariate Analyses ◽  
Reproductive Mode ◽  
Polyploid Complex ◽  
Adaxial Surface ◽  
History Of

Taxa included in the Antennaria monocephala DC. polyploid complex were previously circumscribed at the specific, subspecific, or varietal levels without concensus. The purpose of this phenetic study was to construct a taxonomy that not only reflects the presumed evolutionary history of the complex but also presents a taxonomy that is both functional and informative, regardless of an individual's gender or more importantly, the reproductive mode of the population. The rank of subspecies (A. monocephala ssp. monocephala and A. monocephala ssp. angustata (Green) Hultén) was accepted as the most appropriate level of gender independent circumscription that satisfied the purpose of the phenetic study. These subspecies differ with respect to tomentum, chromosome number, reproductive biology, and (in part) provenance. The former taxon, A. monocephala ssp. monocephala, is a sexual diploid (2n = 28); the latter taxon, A. monocephala ssp. augustata, is an apomictic polyploid, with chromosome numbers ranging from tetraploid (2n = 56) to octoploid (2n = 112). In A. monocephala ssp. monocephala the adaxial surface of the basal and cauline leaves is glabrous-strigose, as is the stem. In A. monocephala ssp. angustata the adaxial surface of both basal and cauline leaves is floccose-tomentose, as is the surface of the stem. Key words: Antennaria monocephala polyploid complex, multivariate analyses.

Reconstructing ancestral chromosome numbers and inflorescence features in Eleusininae (Poaceae: Chloridoideae: Cynodonteae)

2020 ◽  
Vol 193 (3) ◽  
pp. 402-418
Author(s):  
Raquel B Chiavegatto ◽  
Angelino Carta ◽  
Diego G S Pereira ◽  
Flavio R G Benites ◽  
Vânia H Techio ◽  
...  
Keyword(s):  
Chromosome Number ◽  
Chromosome Numbers ◽  
Evolutionary History ◽  
Basic Chromosome Number ◽  
High Rate ◽  
Recent Common Ancestor ◽  
Basic Chromosome ◽  
Most Recent Common Ancestor ◽  
Chromosome Number Evolution ◽  
History Of

Abstract The chromosome number in Poaceae has changed widely over 77 Myr of evolution and polyploidization. Chromosome number changes can suggest a high rate of diversification and evolutionary novelties, and such changes can contribute to speciation. Despite this, chromosome numbers alone do not allow the evolutionary history of a group to be traced. Combined phylogenetic and karyological analyses can clarify the evolutionary history of taxa and allow taxonomic relationships and hierarchical levels to be inferred. The subtribe Eleusininae is the largest of the subfamily Chloridoideae. This study aims to reconstruct their chromosome number evolution, for which ChromEvol 2.0 software was used. Haploid chromosome numbers of Eleusininae were retrieved from the literature, and a consensus phylogenetic tree of Eleusininae was reconstructed. It was possible to infer 41 events of chromosome rearrangements along the evolutionary history of Eleusininae, according to the probabilistic model used. Chromosome number evolution in Eleusininae was mainly influenced by polyploidy events. The ancestral basic chromosome number for Eleusininae was p = 6, but the most recent common ancestor showed p2 = 10. In addition, some derived basic chromosome numbers, such as x = 9, arose through dysploidy, whereas x = 20 was generated via polyploidy.

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