scholarly journals A zombie LIF gene in elephants is up-regulated by TP53 to induce apoptosis in response to DNA damage

2017 ◽  
Author(s):  
Juan Manuel Vazquez ◽  
Michael Sulak ◽  
Sravanthi Chigurupati ◽  
Vincent J. Lynch
Keyword(s):  
Dna Damage ◽  
Body Size ◽  
Cancer Risk ◽  
Leukemia Inhibitory Factor ◽  
Phylogenetic Analyses ◽  
Large Body ◽  
Response Element ◽  
Increased Risk ◽  
Stem Lineage ◽  
Body Sizes

AbstractLarge bodied organisms have more cells that can potentially turn cancerous than smallbodied organisms with fewer cells, imposing an increased risk of developing cancer. This expectation predicts a positive correlation between body size and cancer risk, however, there is no correlation between body size and cancer risk across species (‘Peto’s Paradox’). Here we show that elephants and their extinct relatives (Proboscideans) may have resolved Peto’s Paradox in part through re-functionalizing a leukemia inhibitory factor pseudogene (LIF6) with pro-apoptotic functions. The LIF6 gene is transcriptionally up-regulated by TP53 in response to DNA damage, and translocates to the mitochondria where it induces apoptosis. Phylogenetic analyses of living and extinct Proboscidean LIF6 genes indicates its TP53 response element evolved coincident with the evolution of large body sizes in the Proboscidean stem-lineage. These results suggest that re-functionalizing of a pro-apoptotic LIF pseudogene may have been permissive (though not sufficient) for the evolution of large body sizes in Proboscideans.

scholarly journals TP53 copy number expansion is associated with the evolution of increased body size and an enhanced DNA damage response in elephants

eLife ◽  
2016 ◽  
Vol 5 ◽  
Author(s):  
Michael Sulak ◽  
Lindsey Fong ◽  
Katelyn Mika ◽  
Sravanthi Chigurupati ◽  
Lisa Yon ◽  
...  
Keyword(s):  
Dna Damage ◽  
Body Size ◽  
Signaling Pathway ◽  
Copy Number ◽  
Large Body ◽  
Genotoxic Stress ◽  
Suppressor Gene ◽  
Direct Role ◽  
Increased Risk ◽  
Body Sizes

A major constraint on the evolution of large body sizes in animals is an increased risk of developing cancer. There is no correlation, however, between body size and cancer risk. This lack of correlation is often referred to as 'Peto's Paradox'. Here, we show that the elephant genome encodes 20 copies of the tumor suppressor gene TP53 and that the increase in TP53 copy number occurred coincident with the evolution of large body sizes, the evolution of extreme sensitivity to genotoxic stress, and a hyperactive TP53 signaling pathway in the elephant (Proboscidean) lineage. Furthermore, we show that several of the TP53 retrogenes (TP53RTGs) are transcribed and likely translated. While TP53RTGs do not appear to directly function as transcription factors, they do contribute to the enhanced sensitivity of elephant cells to DNA damage and the induction of apoptosis by regulating activity of the TP53 signaling pathway. These results suggest that an increase in the copy number of TP53 may have played a direct role in the evolution of very large body sizes and the resolution of Peto's paradox in Proboscideans.

scholarly journals TP53copy number expansion is associated with the evolution of increased body size and an enhanced DNA damage response in elephants

2015 ◽  
Author(s):  
Michael Sulak ◽  
Lindsey Fong ◽  
Katelyn Mika ◽  
Sravanthi Chigurupati ◽  
Lisa Yon ◽  
...  
Keyword(s):  
Dna Damage ◽  
Body Size ◽  
Signaling Pathway ◽  
Copy Number ◽  
Large Body ◽  
Genotoxic Stress ◽  
Suppressor Gene ◽  
Direct Role ◽  
Increased Risk ◽  
Body Sizes

SUMMARYA major constraint on the evolution of large body sizes in animals is an increased risk of developing cancer. There is no correlation, however, between body size and cancer risk. This lack of correlation is often referred to as ‘Peto’s Paradox’. Here we show that the elephant genome encodes 20 copies of the tumor suppressor geneTP53and that the increase inTP53copy number occurred coincident with the evolution of large body sizes, the evolution of extreme sensitivity to genotoxic stress, and a hyperactive TP53 signaling pathway in the elephant (Proboscidean) lineage. Furthermore we show that several of theTP53retrogenes (TP53RTGs) are transcribed and likely translated. WhileTP53RTGsdo not appear to directly function as transcription factors, they do contribute to the enhanced sensitivity of elephant cells to DNA damage and the induction of apoptosis by regulating activity of the TP53 signaling pathway. These results suggest that an increase in the copy number ofTP53may have played a direct role in the evolution of very large body sizes and the resolution of Peto’s paradox in Proboscideans.

scholarly journals Large neotheropods from the Upper Triassic of North America and the early evolution of large theropod body sizes

2019 ◽  
Vol 93 (5) ◽  
pp. 1010-1030 ◽  
Author(s):  
Christopher T. Griffin
Keyword(s):  
Body Size ◽  
Phylogenetic Analyses ◽  
Large Body ◽  
Upper Triassic ◽  
Early Evolution ◽  
Phylogenetic Position ◽  
Ancestral State ◽  
Femur Length ◽  
Theropod Dinosaurs ◽  
Body Sizes

AbstractLarge body sizes among nonavian theropod dinosaurs is a major feature in the evolution of this clade, with theropods reaching greater sizes than any other terrestrial carnivores. However, the early evolution of large body sizes among theropods is obscured by an incomplete fossil record, with the largest Triassic theropods represented by only a few individuals of uncertain ontogenetic stage. Here I describe two neotheropod specimens from the Upper Triassic Bull Canyon Formation of New Mexico and place them in a broader comparative context of early theropod anatomy. These specimens possess morphologies indicative of ontogenetic immaturity (e.g., absence of femoral bone scars, lack of co-ossification between the astragalus and calcaneum), and phylogenetic analyses recover these specimens as early-diverging neotheropods in a polytomy with other early neotheropods at the base of the clade. Ancestral state reconstruction for body size suggests that the ancestral theropod condition was small (~240 mm femur length), but the ancestral neotheropod was larger (~300–340 mm femur length), with coelophysoids experiencing secondary body size reduction, although this is highly dependent on the phylogenetic position of a few key taxa. Theropods evolved large body sizes before the Triassic–Jurassic extinction, as hypothesized in most other ancestral state reconstructions of theropod body sizes, but remained rare relative to smaller theropods until the Jurassic.

scholarly journals Genetic testing of dogs predicts problem behaviors in clinical and nonclinical samples

2020 ◽  
Author(s):  
Isain Zapata ◽  
M. Leanne Lilly ◽  
Meghan E. Herron ◽  
James A. Serpell ◽  
Carlos E. Alvarez
Keyword(s):  
Body Size ◽  
Problem Behaviors ◽  
Small Body ◽  
Community Sample ◽  
Large Body ◽  
Second Phase ◽  
Logistic Regression Models ◽  
Individual Level ◽  
Increased Risk ◽  
Phenotype Data

AbstractVery little is known about the etiology of personality and psychiatric disorders. Because the core neurobiology of many such traits is evolutionarily conserved, dogs present a powerful model. We previously reported genome scans of breed averages of ten traits related to fear, anxiety, aggression and social behavior in multiple cohorts of pedigree dogs. As a second phase of that discovery, here we tested the ability of markers at 13 of those loci to predict canine behavior in a community sample of 397 pedigree and mixed-breed dogs with individual-level genotype and phenotype data. We found support for all markers and loci. By including 122 dogs with veterinary behavioral diagnoses in our cohort, we were able to identify eight loci associated with those diagnoses. Logistic regression models showed subsets of those loci could predict behavioral diagnoses. We corroborated our previous findings that small body size is associated with many problem behaviors and large body size is associated with increased trainability. Children in the home were associated with anxiety traits; illness and other animals in the home with coprophagia; working-dog status with increased energy and separation-related problems; and competitive dogs with increased aggression directed at familiar dogs, but reduced fear directed at humans and unfamiliar dogs. Compared to other dogs, Pit Bull-type dogs were not defined by a set of our markers and were not more aggressive; but they were strongly associated with pulling on the leash. Using severity-threshold models, Pit Bull-type dogs showed reduced risk of owner-directed aggression (75th quantile) and increased risk of dog-directed fear (95th quantile). Our findings have broad utility, including for clinical and breeding purposes, but we caution that thorough understanding is necessary for their interpretation and use.

scholarly journals Size- and sex-specific predation on dung flies by amphibian and arthropod predators – size match matters

2019 ◽  
Author(s):  
Wolf U. Blanckenhorn ◽  
Gabriele Cozzi ◽  
Gregory Jäggli ◽  
Juan Pablo Busso
Keyword(s):  
Body Size ◽  
Sexual Size Dimorphism ◽  
Rana Temporaria ◽  
Large Body ◽  
Mechanistic Study ◽  
Mating Activity ◽  
Size Dimorphism ◽  
Arthropod Predators ◽  
Body Sizes ◽  
Predation Rates

Because predator-prey interactions in nature are multifarious, linking phenomenological predation rates to the underlying behavioural or ecological mechanisms is challenging. Size- and sex-specific predation has been implicated as a major selective force keeping animals small, affecting the evolution of body size and sexual size dimorphism. We experimentally assessed predation by various amphibian (frogs and toads) and arthropod predators (bugs, flies, spiders) on three species of dung flies with similar ecology but contrasting body sizes, sexual size dimorphism and coloration. Predators were offered a size range of flies in single- or mixed-sex groups. As expected based on optimal foraging theory, some anurans (e.g. Bufo bufo) selected larger prey, thus selecting against large body size of the flies, while others (Bombina variagata and Rana esculenta) showed no such pattern. Small juvenile Rana temporaria metamorphs, in contrast, preferred small flies, as did all arthropod predators, a pattern that can be explained by larger prey being better at escaping. The more mobile males were not eaten more frequently or faster than the cryptic females, even when conspicuously colored. Predation rates on flies in mixed groups permitting mating activity were not higher, contrary to expectation, nor was predation generally sex-specific. We conclude that the size-selectivity of predators, and hence the viability selection pattern exerted on their prey, depends foremost on the relative body sizes of the two in a continuous fashion. Sex-specific predation by single predators appears to contribute little to sexual dimorphism. Therefore, the mechanistic study of predation requires integration of both the predator’s and the prey’s perspectives, and phenomenological field studies of predation remain indispensable.

“She was neither unduly fat nor lanky”: Representation of body size and beauty in the novels of Daniel O. Fágúnwà

2020 ◽  
Vol 18 (1) ◽  
pp. 131-147
Author(s):  
Fausat Motunrayo Ibrahim ◽  
Ayodele S. Jegede
Keyword(s):  
Body Size ◽  
Large Body ◽  
African Literature ◽  
Thin Structure ◽  
Self Worth ◽  
Body Sizes ◽  
Definition Of

The climate of thought regarding beauty characterization among Africans and other people of colour portrays the large body as beautiful. This reflects that body size and beauty is racially and culturally expressive, making it apposite to be disparate in advancing related discourses. This is particularly important because such discourses can influence Africans’ evaluation of their self-worth. The concerns generated by the global rise in obesity further create interest in these issues. African literature offers a fine and disparate platform to understand social realities. Consequently, relevant contents of the five precedent Yorùbá novels of Daniel Fágúnwà including Igbó Olódùmarè, Ìrèké Oníbùdó,Ògbójú ọdẹ nínú Igbó Irúnmọlè, Ìrìnkèrindò nínú Igbó Elégbèje and Àdììtú Olódùmarè were extracted and analyzed to examine association of beauty with body sizes. Findings reflect more of bipolarity in the definition of beauty, such that the none-fat/none-thin structure is conveyed as beautiful. Concurrently, the fat and the thin is also portrayed as beautiful, making ‘body size’ definition of beauty to be elusive, and strongly suggesting neutrality to body size among the Yorùbá. This is strongly borne out of Fágúnwà’s and indeed, Yorùbá construction of beauty from a ‘character’ perspective. Character (ìwà) is staunchly expounded as constituting beauty. The beautiful body size is indeterminate in Fágúnwà’s narratives and indeed, in Yorùbá thought.

Prey preference of a wasp determined by nest size supports the role of natural selection in body size evolution in Cassidinae leaf beetles

2021 ◽  
Author(s):  
Tadashi Shinohara ◽  
Yasuoki Takami
Keyword(s):  
Body Size ◽  
Natural Selection ◽  
Prey Species ◽  
Large Body ◽  
Size Variation ◽  
Prey Preference ◽  
Nest Size ◽  
Large Prey ◽  
Leaf Beetles ◽  
Body Sizes

Abstract The prey preference of a predator can impose natural selection on prey phenotypes, including body size. Despite evidence that large body size protects against predation in insects, the determinants of body size variation in Cassidinae leaf beetles are not well understood. We examined the prey preference of the digger wasp Cerceris albofasciata, a specialist predator of adult Cassidinae leaf beetles, and found evidence for natural selection on prey body size. The wasp hunted prey smaller than the size of their nest entrance. However, the wasp preferred larger prey species among those that could be carried into their nest. Thus, the benefits of large prey and the cost associated with nest expansion might determine the prey size preference. As expected from the prey species preference, the wasp preferred small individuals of the largest prey species, Thlaspida biramosa, and large individuals of the smallest prey species, Cassida piperata, resulting in natural selection on body sizes. In intermediate-sized prey species, however, there was no evidence for selection on body size. Natural selection on body size might explain the variation of prey morphologies that increase body size, such as explanate margins, in this group.

Traditional Attenuation of Inequality: Neutral Meaning of Body Size among the Yorùbá of Southwestern Nigeria

2020 ◽  
pp. 1-25
Author(s):  
Fausat M. Ibrahim ◽  
Ayodele S. Jegede
Keyword(s):  
Body Size ◽  
Phenomenological Study ◽  
Large Body ◽  
Human Person ◽  
Group Discussions ◽  
Southwestern Nigeria ◽  
Good Person ◽  
Body Sizes ◽  
Globalized World ◽  
Depth Interviews

Abstract Body size is a profound ground of inequality in modern global society. Moreover, constructions of body size are racially polarized, with blacks being reputed for venerating large body. Proceeding with a triangulation of qualitative methods, this phenomenological study featured forty-two in-depth interviews, eight focus group discussions and eighteen key informant interviews among men and women of varying body sizes in two of the six states of southwestern Nigeria. Findings reflect dominantly neutral meaning of body size among the Yorùbá. This neutrality is dominantly reflected in the literal questioning of meaning that Yorùbá attach to body size, and who becomes a king in Yorùbá land but partially neutral in acceptability of prospective son or daughter in-law. Divinity, orí (fate), ìwà (good behavior) and ọmọlúàbí (good person) are among phenomena that counts in discerning people’s worth. Meaning attached to body size is opposed to common-place attitude to body size, making this attitude to be profane while meaning is solemn. This meaning is tremendously in favour of optimum health, and attenuating inequality, for which even black societies are perpetrating in the globalized world. Traditional Yorùbá value of human person is irrespective of body size.

Body Size, Adaptation and Function

1989 ◽  
Vol 48 (1) ◽  
pp. 15-20 ◽  
Author(s):  
Reynaldo Martorell
Keyword(s):  
Developing Countries ◽  
Body Size ◽  
Cognitive Development ◽  
Growth Retardation ◽  
Small Body ◽  
Warning Signal ◽  
Increased Risk ◽  
Body Sizes ◽  
And Function ◽  
Excellent Tool

This is a brief discussion of the "small but healthy" hypothesis proposed by David Seckler in the early 1980s. Four basic points are made. First, adults in developing countries have small body sizes largely as a result of poor diets and infection during childhood. Therefore, to acclaim small body sizes as a desirable attribute for populations is also to affirm that its causes are desirable. Second, monitoring the growth of children is widely recognized as an excellent tool for detecting health problems. Growth retardation, rather than an innocuous response to environmental stimuli, is a warning signal of increased risk of morbidity and mortality. Third, the conditions which give rise to stunted children also affect other aspects such as cognitive development. Finally, stunted girls who survive to be short women are at greater risk of delivering growth retarded infants with a greater probability of dying in infancy. For all these reasons, small is not healthy.

scholarly journals Predation selectively culls medium-sized species from island mammal faunas

2014 ◽  
Vol 10 (4) ◽  
pp. 20131066 ◽  
Author(s):  
Emily Hanna ◽  
Marcel Cardillo
Keyword(s):  
Body Size ◽  
Extinction Risk ◽  
Large Body ◽  
Conservation Strategies ◽  
Size Selectivity ◽  
Introduced Predators ◽  
Body Sizes ◽  
Mammal Faunas ◽  
Species Declines ◽  
Risk Association

Globally, elevated extinction risk in mammals is strongly associated with large body size. However, in regions where introduced predators exert strong top-down pressure on mammal populations, the selectivity of extinctions may be skewed towards species of intermediate body size, leading to a hump-shaped relationship between size and extinction risk. The existence of this kind of extinction pattern, and its link to predation, has been contentious and difficult to demonstrate. Here, we test the hypothesis of a hump-shaped body size–extinction relationship, using a database of 927 island mammal populations. We show that the size-selectivity of extinctions on many islands has exceeded that expected under null models. On islands with introduced predators, extinctions are biased towards intermediate body sizes, but this bias does not occur on islands without predators. Hence, on islands with a large-bodied mammal fauna, predators are selectively culling species from the lower end of the size distribution, and on islands with a small-bodied fauna they are culling species from the upper end. These findings suggest that it will be difficult to use predictable generalizations about extinction patterns, such as a positive body size–extinction risk association, to anticipate future species declines and plan conservation strategies accordingly.

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