Comparative osteohistology of some embryonic and perinatal archosaurs: developmental and behavioral implications for dinosaurs

Histologic studies of embryonic and perinatal longbones of living birds, non-avian dinosaurs, and other reptiles show a strong phylogenetic signal in the distribution of tissues and patterns of vascularization in both the shafts and the bone ends. The embryonic bones of basal archosaurs and other reptiles have thin-walled cortices and large marrow cavities that are sometimes subdivided by erosion rooms in early stages of growth. The cortices of basal reptiles are poorly vascularized, and osteocyte lacunae are common but randomly organized. Additionally, there is no evidence of fibrolamellar tissue organization around the vascular spaces. Compared with turtles, basal archosaurs show an increase in vascularization, better organized osteocytes, and some fibrolamellar tissue organization. In dinosaurs, including birds, vascularization is greater than in basal archosaurs, as is cortical thickness, and the osteocyte lacunae are more abundant and less randomly organized. Fibrolamellar tissues are evident around vascular canals and form organized primary osteons in older perinates and juveniles.Metaphyseal (“epiphyseal”) morphology varies with the acquisition of new features in derived groups. The cartilage cone, persistent through the Reptilia (crown-group reptiles, including birds), is completely calcified in ornithischian dinosaurs before it is eroded by marrow processes; cartilage canals, absent in basal archosaurs, are present in Dinosauria; a thickened calcified hypertrophy zone in Dinosauria indicates an acceleration of longitudinal bone growth.Variations in this set of histological synapomorphies overlap between birds and non-avian dinosaurs. In birds, these variations are strongly correlated with life-history strategies. This overlap, plus independent evidence from nesting sites, reinforces the hypothesis that variations in bone growth strategies in Mesozoic dinosaurs reflect different life-history strategies, including nesting behavior of neonates and parental care.

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Evolutionary heritage influences Amazon tree ecology

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2016.1587 ◽

2016 ◽

Vol 283 (1844) ◽

pp. 20161587 ◽

Cited By ~ 21

Author(s):

Fernanda Coelho de Souza ◽

Kyle G. Dexter ◽

Oliver L. Phillips ◽

Roel J. W. Brienen ◽

Jerome Chave ◽

...

Keyword(s):

Life History ◽

Evolutionary History ◽

Large Scale ◽

Phylogenetic Signal ◽

Life History Strategies ◽

Relative Importance ◽

Life History Variation ◽

Trait Variation ◽

Closed Canopy ◽

Repeated Evolution

Lineages tend to retain ecological characteristics of their ancestors through time. However, for some traits, selection during evolutionary history may have also played a role in determining trait values. To address the relative importance of these processes requires large-scale quantification of traits and evolutionary relationships among species. The Amazonian tree flora comprises a high diversity of angiosperm lineages and species with widely differing life-history characteristics, providing an excellent system to investigate the combined influences of evolutionary heritage and selection in determining trait variation. We used trait data related to the major axes of life-history variation among tropical trees (e.g. growth and mortality rates) from 577 inventory plots in closed-canopy forest, mapped onto a phylogenetic hypothesis spanning more than 300 genera including all major angiosperm clades to test for evolutionary constraints on traits. We found significant phylogenetic signal (PS) for all traits, consistent with evolutionarily related genera having more similar characteristics than expected by chance. Although there is also evidence for repeated evolution of pioneer and shade tolerant life-history strategies within independent lineages, the existence of significant PS allows clearer predictions of the links between evolutionary diversity, ecosystem function and the response of tropical forests to global change.

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Relationship between bone growth rate and bone tissue organization in amniotes: first test of Amprino's rule in a phylogenetic context

Animal Biology ◽

10.1163/157075610x12610595764093 ◽

2010 ◽

Vol 60 (1) ◽

pp. 25-41 ◽

Cited By ~ 31

Author(s):

Jacques Castanet ◽

Jorge Cubo ◽

Laëtitia Montes

Keyword(s):

Growth Rate ◽

Bone Tissue ◽

Growth Rates ◽

Bone Growth ◽

Phylogenetic Signal ◽

Variation Partitioning ◽

High Growth ◽

Tissue Organization ◽

Shared Ancestry ◽

Functional Factors

AbstractA debate on the determinism (phylogenetic versus functional) of the diversity of bone histological features has centred the interest of bone comparative biologists. While some authors have noticed the presence of a phylogenetic signal in bone tissue variation, many others have argued that these characters may not include much phylogenetic information, but rather reflect functional factors. Here we quantify both components in a sample of amniotes. We hypothesize that: 1/ the observed variation is partly the outcome of shared ancestry (phylogenetic factor) and 2/ for a given quantity of bone produced, tissues formed at a rapid rate may have a higher fraction of vascular cavities than those produced at a slower rate (functional factor). Variation partitioning analyses show that the phylogeny explains a significant portion of the variation of bone vascularity (85.3%), bone growth rate also explains a significant portion of this variation (68.3%), and there is an important overlap (67.9%). Finally, an optimization through least-squares parsimony of bone growth rates onto the phylogeny shows that the most important evolutionary change may have occurred after the split between crocodiles and birds. This change may be linked to the origin of avian endothermic metabolism because high growth rates involve high protein turnover, which is very energy consuming. We conclude that the debate on the dichotomy between phylogenetic versus functional causation of bone histological diversity is misleading, because we have shown that bone vascularity has, at the same time, a functional significance and a phylogenetic signal.

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The evolution of red blood cell shape in a continental radiation of fishes

10.1101/2020.04.03.023994 ◽

2020 ◽

Author(s):

Brenda Oliveira Martins ◽

Lilian Franco-Belussi ◽

Mayara Schueroff Siqueira ◽

Carlos E. Fernandes ◽

Diogo B. Provete

Keyword(s):

Life History ◽

Water Column ◽

Phylogenetic Relationship ◽

Phylogenetic Signal ◽

Life History Strategies ◽

Selective Pressures ◽

Components Analysis ◽

Dated Phylogeny ◽

Nucleus Volume

AbstractThe size and shape of Red Blood Cells (RBC) can provide key information on life history strategies in vertebrates. However, little is known about how RBC shape evolved in response to environmental factors and the role of phylogenetic relationship. Here, we analyzed RBC morphometrics in a continental radiation of fishes testing the hypothesis that phylogenetic relationship determines species occupation of morphospace. We collected blood samples of five specimens of 15 freshwater fish species from six orders and used basic stereological methods to measure cell and nucleus area, perimeter, and diameter, cell and nucleus volume, nucleus:cytoplasm ratio, and shape factor of 50 cells per specimen. Then, we conducted a phylogenetic Principal Components Analysis using a dated phylogeny and built a phylomorphospace. To test if the phylogenetic relationship predicted the phenotypic similarity of species, we calculated multivariate phylogenetic signal. We also estimated the evolution rate of RBC shape for each node and tip using ridge regression. Finally, we tested if the position in the water column influenced RBC shape using a phylogenetic GLS. RBC shape seems to have evolved in a non-stationary way because the distribution pattern of species in the phylomorphospace is independent of the phylogeny. Accordingly, the rate of evolution for shape was highly heterogeneous, with an increase in the genus Pygocentrus. Water column position does not influence RBC shape. In conclusion, RBC shape seem to have evolved in response to multiple selective pressures independent of life history characters.

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Growth forms and life-history strategies predict the occurrence of aquatic macrophytes in relation to environmental factors in a shallow peat lake complex

Hydrobiologia ◽

10.1007/s10750-021-04618-6 ◽

2021 ◽

Author(s):

Ralph J. M. Temmink ◽

Martijn Dorenbosch ◽

Leon P. M. Lamers ◽

Alfons J. P. Smolders ◽

Winnie Rip ◽

...

Keyword(s):

Life History ◽

Environmental Factors ◽

Water Depth ◽

Growth Form ◽

Aquatic Vegetation ◽

Critical Role ◽

Species Selection ◽

Life History Strategies ◽

Growth Strategies ◽

Growth Forms

AbstractAquatic ecosystems provide vital services, and macrophytes play a critical role in their functioning. Conceptual models indicate that in shallow lakes, plants with different growth strategies are expected to inhabit contrasting habitats. For shallow peat lakes, characterized by incohesive sediments, roles of growth forms, life-history strategies and environmental factors in determining the occurrence of aquatic vegetation remain unknown. In a field survey, we sampled 64 points in a peat lake complex and related macrophyte occurrence to growth forms (floating-leaved rooted and submerged), life-history strategies for overwintering (turions, seeds, rhizomes) and environmental factors (water depth, fetch, and porewater nutrients). Our survey showed that macrophyte occurrence relates to water depth, wind-fetch, and nutrients, and depends on growth form and life-history strategies. Specifically, rooted floating-leaved macrophytes occur at lower wind-fetch/shallower waters. Submerged macrophytes occur from low to greater wind-fetch/water depth, depending on life-history strategies; macrophytes with rhizomes occur at greater wind-fetch/depth relative to species that overwinter with seeds or turions. We conclude that growth form and life-history strategies for overwintering predict macrophytes occurrence regarding environmental factors in peat lakes. Therefore, we propose an adapted model for macrophyte occurrence for such lakes. Altogether, these results may aid in species-selection to revegetate peat lakes depending on its environment.

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Exposure to glucocorticoids alters life history strategies in a facultatively paedomorphic salamander

Journal of Experimental Zoology Part A Ecological and Integrative Physiology ◽

10.1002/jez.2445 ◽

2021 ◽

Author(s):

Jason R. Bohenek ◽

Christopher J. Leary ◽

William J. Resetarits

Keyword(s):

Life History ◽

Life History Strategies

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Natural variation in plant telomere length is associated with flowering time

The Plant Cell ◽

10.1093/plcell/koab022 ◽

2021 ◽

Author(s):

Jae Young Choi ◽

Liliia R Abdulkina ◽

Jun Yin ◽

Inna B Chastukhina ◽

John T Lovell ◽

...

Keyword(s):

Life History ◽

Telomere Length ◽

Flowering Time ◽

Dna Sequences ◽

Genome Wide Association Study ◽

Genomic Analysis ◽

Life History Strategies ◽

Length Variation ◽

Chromosomal Structure ◽

Chromosome Integrity

Abstract Telomeres are highly repetitive DNA sequences found at the ends of chromosomes that protect the chromosomes from deterioration during cell division. Here, using whole genome re-sequencing and terminal restriction fragment assays, we found substantial natural intraspecific variation in telomere length in Arabidopsis thaliana, rice (Oryza sativa), and maize (Zea mays). Genome-wide association study (GWAS) mapping in A. thaliana identified 13 regions with GWAS-significant associations underlying telomere length variation, including a region that harbors the telomerase reverse transcriptase (TERT) gene. Population genomic analysis provided evidence for a selective sweep at the TERT region associated with longer telomeres. We found that telomere length is negatively correlated with flowering time variation not only in A. thaliana, but also in maize and rice, indicating a link between life history traits and chromosome integrity. Our results point to several possible reasons for this correlation, including the possibility that longer telomeres may be more adaptive in plants that have faster developmental rates (and therefore flower earlier). Our work suggests that chromosomal structure itself might be an adaptive trait associated with plant life history strategies.

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