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1.
Annu Rev Cell Dev Biol ; 30: 535-60, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25062362

RESUMEN

Although most modern dog breeds are less than 200 years old, the symbiosis between man and dog is ancient. Since prehistoric times, repeated selection events have transformed the wolf into man's guardians, laborers, athletes, and companions. The rapid transformation from pack predator to loyal companion is a feat that is arguably unique among domesticated animals. How this transformation came to pass remained a biological mystery until recently: Within the past decade, the deployment of genomic approaches to study population structure, detect signatures of selection, and identify genetic variants that underlie canine phenotypes is ushering into focus novel biological mechanisms that make dogs remarkable. Ironically, the very practices responsible for breed formation also spurned morbidity; today, many diseases are correlated with breed identity. In this review, we discuss man's best friend in the context of a genetic model to understand paradigms of heritable phenotypes, both desirable and disadvantageous.


Asunto(s)
Perros/genética , Genoma , Animales , Tamaño Corporal/genética , Neoplasias Óseas/genética , Neoplasias Óseas/veterinaria , Cruzamiento , Mapeo Cromosómico , Modelos Animales de Enfermedad , Enfermedades de los Perros/genética , Perros/anatomía & histología , Perros/clasificación , Extremidades/anatomía & histología , Estudio de Asociación del Genoma Completo , Glicoproteínas/genética , Glicoproteínas/fisiología , Proteína HMGA2/genética , Proteína HMGA2/fisiología , Cabello/anatomía & histología , Cardiopatías/genética , Cardiopatías/veterinaria , Péptidos y Proteínas de Señalización Intercelular/genética , Péptidos y Proteínas de Señalización Intercelular/fisiología , Síndromes Neoplásicos Hereditarios/genética , Síndromes Neoplásicos Hereditarios/veterinaria , Osteosarcoma/genética , Osteosarcoma/veterinaria , Fenotipo , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Selección Genética , Piel/anatomía & histología , Cráneo/anatomía & histología , Proteína Smad2/genética , Proteína Smad2/fisiología , Especificidad de la Especie , Cola (estructura animal)/anatomía & histología
2.
Development ; 151(20)2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-38980277

RESUMEN

Many animals share a lifelong capacity to adapt their growth rates and body sizes to changing environmental food supplies. However, the cellular and molecular basis underlying this plasticity remains only poorly understood. We therefore studied how the sea anemones Nematostella vectensis and Aiptasia (Exaiptasia pallida) respond to feeding and starvation. Combining quantifications of body size and cell numbers with mathematical modelling, we observed that growth and shrinkage rates in Nematostella are exponential, stereotypic and accompanied by dramatic changes in cell numbers. Notably, shrinkage rates, but not growth rates, are independent of body size. In the facultatively symbiotic Aiptasia, we show that growth and cell proliferation rates are dependent on the symbiotic state. On a cellular level, we found that >7% of all cells in Nematostella juveniles reversibly shift between S/G2/M and G1/G0 cell cycle phases when fed or starved, respectively. Furthermore, we demonstrate that polyp growth and cell proliferation are dependent on TOR signalling during feeding. Altogether, we provide a benchmark and resource for further investigating the nutritional regulation of body plasticity on multiple scales using the genetic toolkit available for Nematostella.


Asunto(s)
Tamaño Corporal , Proliferación Celular , Anémonas de Mar , Animales , Anémonas de Mar/citología , Anémonas de Mar/fisiología , Ciclo Celular/fisiología , Conducta Alimentaria/fisiología , Transducción de Señal , Simbiosis , Serina-Treonina Quinasas TOR/metabolismo
3.
Proc Natl Acad Sci U S A ; 120(9): e2217904120, 2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36802425

RESUMEN

We consider the distribution of fruit pigeons of the genera Ptilinopus and Ducula on the island of New Guinea. Of the 21 species, between six and eight coexist inside humid lowland forests. We conducted or analyzed 31 surveys at 16 different sites, resurveying some sites in different years. The species coexisting at any single site in a single year are a highly nonrandom selection of the species to which that site is geographically accessible. Their sizes are both much more widely spread and more uniformly spaced than in random sets of species drawn from the locally available species pool. We also present a detailed case study of a highly mobile species that has been recorded on every ornithologically explored island in the West Papuan island group west of New Guinea. That species' rareness on just three well-surveyed islands within the group cannot be due to an inability to reach them. Instead, its local status decreases from abundant resident to rare vagrant in parallel with increasing weight proximity of the other resident species.


Asunto(s)
Columbidae , Bosques , Animales , Nueva Guinea
4.
Proc Natl Acad Sci U S A ; 120(50): e2310855120, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38048453

RESUMEN

Mammals play important ecological roles in terrestrial ecosystems, with their particular niches and their impacts on energy flow and nutrient cycling being strongly influenced by one of their most fundamental traits-their body size. Body size influences nearly all of the physiological, behavioral, and ecological traits of mammals, and thus, shifts in body size often serve as key mechanisms of adaptation to variation in environmental conditions over space and time. Along with shifts in phenology and distributions, declining body size has been purported to be one of the three universal responses to anthropogenic climate change, yet few studies have been conducted at the spatial and temporal scales appropriate to test this claim. Here, we report that in response to warming of terrestrial ecosystems across North America over the past century, small mammals are decreasing in body size. We further estimate that by 2100 (when global temperatures may have risen some 2.5 to 5.5 °C since 1880), the total anthropogenic decline in body mass of these ecologically and economically important species may range from 10 to 21%. Such shifts in body size of the great multitudes of small mammal populations are, in turn, likely to have major impacts on the structural and functional diversity of terrestrial assemblages across the globe.


Asunto(s)
Cambio Climático , Ecosistema , Animales , Tamaño Corporal , Mamíferos/fisiología , América del Norte
5.
Proc Natl Acad Sci U S A ; 120(49): e2313224120, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38015844

RESUMEN

The decision to stop growing and mature into an adult is a critical point in development that determines adult body size, impacting multiple aspects of an adult's biology. In many animals, growth cessation is a consequence of hormone release that appears to be tied to the attainment of a particular body size or condition. Nevertheless, the size-sensing mechanism animals use to initiate hormone synthesis is poorly understood. Here, we develop a simple mathematical model of growth cessation in Drosophila melanogaster, which is ostensibly triggered by the attainment of a critical weight (CW) early in the last instar. Attainment of CW is correlated with the synthesis of the steroid hormone ecdysone, which causes a larva to stop growing, pupate, and metamorphose into the adult form. Our model suggests that, contrary to expectation, the size-sensing mechanism that initiates metamorphosis occurs before the larva reaches CW; that is, the critical-weight phenomenon is a downstream consequence of an earlier size-dependent developmental decision, not a decision point itself. Further, this size-sensing mechanism does not require a direct assessment of body size but emerges from the interactions between body size, ecdysone, and nutritional signaling. Because many aspects of our model are evolutionarily conserved among all animals, the model may provide a general framework for understanding how animals commit to maturing from their juvenile to adult form.


Asunto(s)
Proteínas de Drosophila , Drosophila , Animales , Drosophila melanogaster , Ecdisona , Tamaño Corporal , Larva , Metamorfosis Biológica
6.
Proc Natl Acad Sci U S A ; 120(20): e2206971120, 2023 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-37155909

RESUMEN

Variation in evolutionary rates among species is a defining characteristic of the tree of life and may be an important predictor of species' capacities to adapt to rapid environmental change. It is broadly assumed that generation length is an important determinant of microevolutionary rates, and body size is often used as a proxy for generation length. However, body size has myriad biological correlates that could affect evolutionary rates independently from generation length. We leverage two large, independently collected datasets on recent morphological change in birds (52 migratory species breeding in North America and 77 South American resident species) to test how body size and generation length are related to the rates of contemporary morphological change. Both datasets show that birds have declined in body size and increased in wing length over the past 40 y. We found, in both systems, a consistent pattern wherein smaller species declined proportionally faster in body size and increased proportionally faster in wing length. By contrast, generation length explained less variation in evolutionary rates than did body size. Although the mechanisms warrant further investigation, our study demonstrates that body size is an important predictor of contemporary variation in morphological rates of change. Given the correlations between body size and a breadth of morphological, physiological, and ecological traits predicted to mediate phenotypic responses to environmental change, the relationship between body size and rates of phenotypic change should be considered when testing hypotheses about variation in adaptive responses to climate change.


Asunto(s)
Evolución Biológica , Aves , Animales , Aves/fisiología , Tamaño Corporal/fisiología , Cambio Climático , Adaptación Fisiológica
7.
Dev Biol ; 509: 59-69, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38373693

RESUMEN

Mg2+ is a vital ion involved in diverse cellular functions by forming complexes with ATP. Intracellular Mg2+ levels are tightly regulated by the coordinated actions of multiple Mg2+ transporters, such as the Mg2+ efflux transporter, cyclin M (CNNM). Caenorhabditis elegans (C. elegans) worms with mutations in both cnnm-1 and cnnm-3 exhibit excessive Mg2+ accumulation in intestinal cells, leading to various phenotypic abnormalities. In this study, we investigated the mechanism underlying the reduction in body size in cnnm-1; cnnm-3 mutant worms. RNA interference (RNAi) of gtl-1, which encodes a Mg2+-intake channel in intestinal cells, restored the worm body size, confirming that this phenotype is due to excessive Mg2+ accumulation. Moreover, RNAi experiments targeting body size-related genes and analyses of mutant worms revealed that the suppression of the target of rapamycin complex 2 (TORC2) signaling pathway was involved in body size reduction, resulting in downregulated DAF-7 expression in head ASI neurons. As the DAF-7 signaling pathway suppresses dauer formation under stress, cnnm-1; cnnm-3 mutant worms exhibited a greater tendency to form dauer upon induction. Collectively, our results revealed that excessive accumulation of Mg2+ repressed the TORC2 signaling pathway in C. elegans worms and suggest the novel role of the DAF-7 signaling pathway in the regulation of their body size.


Asunto(s)
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animales , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Transducción de Señal/genética , Diana Mecanicista del Complejo 2 de la Rapamicina/genética , Diana Mecanicista del Complejo 2 de la Rapamicina/metabolismo , Mutación/genética , Tamaño Corporal/genética
8.
Mol Biol Evol ; 41(8)2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39073613

RESUMEN

Parallel evolution occurs when distinct lineages with similar ancestral states converge on a new phenotype. Parallel evolution has been well documented at the organ, gene pathway, and amino acid sequence level but in theory, it can also occur at individual nucleotides within noncoding regions. To examine the role of parallel evolution in shaping the biology of mammalian complex traits, we used data on single-nucleotide polymorphisms (SNPs) influencing human intraspecific variation to predict trait values in other species for 11 complex traits. We found that the alleles at SNP positions associated with human intraspecific height and red blood cell (RBC) count variation are associated with interspecific variation in the corresponding traits across mammals. These associations hold for deeper branches of mammalian evolution as well as between strains of collaborative cross mice. While variation in RBC count between primates uses both ancient and more recently evolved genomic regions, we found that only primate-specific elements were correlated with primate body size. We show that the SNP positions driving these signals are flanked by conserved sequences, maintain synteny with target genes, and overlap transcription factor binding sites. This work highlights the potential of conserved but tunable regulatory elements to be reused in parallel to facilitate evolutionary adaptation in mammals.


Asunto(s)
Evolución Molecular , Mamíferos , Herencia Multifactorial , Polimorfismo de Nucleótido Simple , Animales , Humanos , Ratones , Mamíferos/genética , Primates/genética , Secuencias Reguladoras de Ácidos Nucleicos , Evolución Biológica , Especificidad de la Especie
9.
Mol Biol Evol ; 41(3)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38376487

RESUMEN

The blue whale, Balaenoptera musculus, is the largest animal known to have ever existed, making it an important case study in longevity and resistance to cancer. To further this and other blue whale-related research, we report a reference-quality, long-read-based genome assembly of this fascinating species. We assembled the genome from PacBio long reads and utilized Illumina/10×, optical maps, and Hi-C data for scaffolding, polishing, and manual curation. We also provided long read RNA-seq data to facilitate the annotation of the assembly by NCBI and Ensembl. Additionally, we annotated both haplotypes using TOGA and measured the genome size by flow cytometry. We then compared the blue whale genome with other cetaceans and artiodactyls, including vaquita (Phocoena sinus), the world's smallest cetacean, to investigate blue whale's unique biological traits. We found a dramatic amplification of several genes in the blue whale genome resulting from a recent burst in segmental duplications, though the possible connection between this amplification and giant body size requires further study. We also discovered sites in the insulin-like growth factor-1 gene correlated with body size in cetaceans. Finally, using our assembly to examine the heterozygosity and historical demography of Pacific and Atlantic blue whale populations, we found that the genomes of both populations are highly heterozygous and that their genetic isolation dates to the last interglacial period. Taken together, these results indicate how a high-quality, annotated blue whale genome will serve as an important resource for biology, evolution, and conservation research.


Asunto(s)
Balaenoptera , Neoplasias , Animales , Balaenoptera/genética , Duplicaciones Segmentarias en el Genoma , Genoma , Demografía , Neoplasias/genética
10.
Development ; 149(6)2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-35195254

RESUMEN

In Drosophila, changes to dietary protein elicit different body size responses between the sexes. Whether these differential body size effects extend to other macronutrients remains unclear. Here, we show that lowering dietary sugar (0S diet) enhanced body size in male and female larvae. Despite an equivalent phenotypic effect between the sexes, we detected sex-specific changes to signalling pathways, transcription and whole-body glycogen and protein. In males, the low-sugar diet augmented insulin/insulin-like growth factor signalling pathway (IIS) activity by increasing insulin sensitivity, where increased IIS was required for male metabolic and body size responses in 0S. In females reared on low sugar, IIS activity and insulin sensitivity were unaffected, and IIS function did not fully account for metabolic and body size responses. Instead, we identified a female-biased requirement for the Target of rapamycin pathway in regulating metabolic and body size responses. Together, our data suggest the mechanisms underlying the low-sugar-induced increase in body size are not fully shared between the sexes, highlighting the importance of including males and females in larval studies even when similar phenotypic outcomes are observed.


Asunto(s)
Proteínas de Drosophila , Resistencia a la Insulina , Animales , Tamaño Corporal , Dieta , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Femenino , Insulina/metabolismo , Larva/metabolismo , Masculino , Azúcares/metabolismo
11.
BMC Genomics ; 25(1): 296, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38509464

RESUMEN

BACKGROUND: Body weight and size are important economic traits in chickens. While many growth-related quantitative trait loci (QTLs) and candidate genes have been identified, further research is needed to confirm and characterize these findings. In this study, we investigate genetic and genomic markers associated with chicken body weight and size. This study provides new insights into potential markers for genomic selection and breeding strategies to improve meat production in chickens. METHODS: We performed whole-genome resequencing of and Wenshang Barred (WB) chickens (n = 596) and three additional breeds with varying body sizes (Recessive White (RW), WB, and Luxi Mini (LM) chickens; (n = 50)). We then used selective sweeps of mutations coupled with genome-wide association study (GWAS) to identify genomic markers associated with body weight and size. RESULTS: We identified over 9.4 million high-quality single nucleotide polymorphisms (SNPs) among three chicken breeds/lines. Among these breeds, 287 protein-coding genes exhibited positive selection in the RW and WB populations, while 241 protein-coding genes showed positive selection in the LM and WB populations. Genomic heritability estimates were calculated for 26 body weight and size traits, including body weight, chest breadth, chest depth, thoracic horn, body oblique length, keel length, pelvic width, shank length, and shank circumference in the WB breed. The estimates ranged from 0.04 to 0.67. Our analysis also identified a total of 2,522 genome-wide significant SNPs, with 2,474 SNPs clustered around two genomic regions. The first region, located on chromosome 4 (7.41-7.64 Mb), was linked to body weight after ten weeks and body size traits. LCORL, LDB2, and PPARGC1A were identified as candidate genes in this region. The other region, located on chromosome 1 (170.46-171.53 Mb), was associated with body weight from four to eighteen weeks and body size traits. This region contained CAB39L and WDFY2 as candidate genes. Notably, LCORL, LDB2, and PPARGC1A showed highly selective signatures among the three breeds of chicken with varying body sizes. CONCLUSION: Overall this study provides a comprehensive map of genomic variants associated with body weight and size in chickens. We propose two genomic regions, one on chromosome 1 and the other on chromosome 4, that could helpful for developing genome selection breeding strategies to enhance meat yield in chickens.


Asunto(s)
Pollos , Estudio de Asociación del Genoma Completo , Animales , Pollos/genética , Sitios de Carácter Cuantitativo , Genómica , Peso Corporal/genética , Fenotipo , Polimorfismo de Nucleótido Simple , China
12.
BMC Genomics ; 25(1): 739, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39080522

RESUMEN

BACKGROUND: Elucidating the genetic variation underlying phenotypic diversity will facilitate improving production performance in livestock species. The Tibetan sheep breed in China holds significant historical importance, serving as a fundamental pillar of Qinghai's animal husbandry sector. The Plateau-type Tibetan sheep, comprising 90% of the province's population, are characterized by their tall stature and serve as the primary breed among Tibetan sheep. In contrast, Zhashijia sheep exhibit larger size and superior meat quality. These two species provide an excellent model for elucidating the genetic basis of body size variation. Therefore, this study aims to conduct a comprehensive genome-wide association study on these two Tibetan sheep breeds to identify single nucleotide polymorphism loci and regulatory genes that influence body size traits in Tibetan sheep. RESULT: In this study, the phenotypic traits of body weight, body length, body height, chest circumference, chest depth, chest width, waist angle width, and pipe circumference were evaluated in two Tibetan sheep breeds: Plateau-type sheep and Zhashijia Tibetan sheep. Whole genome sequencing generated 48,215,130 high-quality SNPs for genome-wide association study. Four methods were applied and identified 623 SNPs significantly associated with body size traits. The significantly associated single nucleotide polymorphisms identified in this study are located near or within 111 candidate genes. These genes exhibit enrichment in the cAMP and Rap1 signaling pathways, significantly affecting animal growth, and body size. Specifically, the following genes were associated: ASAP1, CDK6, FRYL, NAV2, PTPRM, GPC6, PTPRG, KANK1, NTRK2 and ADCY8. CONCLUSION: By genome-wide association study, we identified 16 SNPs and 10 candidate genes associated with body size traits in Tibetan sheep, which hold potential for application in genomic selection breeding programs in sheep. Identifying these candidate genes will establish a solid foundation for applying molecular marker-assisted selection in sheep breeding and improve our understanding of body size control in farmed animals.


Asunto(s)
Tamaño Corporal , Estudio de Asociación del Genoma Completo , Fenotipo , Polimorfismo de Nucleótido Simple , Animales , Tamaño Corporal/genética , Ovinos/genética , Ovinos/anatomía & histología , Tibet , Sitios de Carácter Cuantitativo
13.
Ecol Lett ; 27(1): e14310, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37811596

RESUMEN

Species invasions are predicted to increase in frequency with global change, but quantitative predictions of how environmental filters and species traits influence the success and consequences of invasions for local communities are lacking. Here we investigate how invaders alter the structure, diversity and stability regime of simple communities across environmental gradients (habitat productivity, temperature) and community size structure. We simulate all three-species trophic modules (apparent and exploitative competition, trophic chain and intraguild predation). We predict that invasions most often succeed in warm and productive habitats and that successful invaders include smaller competitors, intraguild predators and comparatively small top predators. This suggests that species invasions and global change may facilitate the downsizing of food webs. Furthermore, we show that successful invasions leading to species substitutions rarely alter system stability, while invasions leading to increased diversity can destabilize or stabilize community dynamics depending on the environmental conditions and invader's trophic position.


Asunto(s)
Ecosistema , Cadena Alimentaria , Animales , Temperatura , Tamaño Corporal , Conducta Predatoria
14.
Mol Biol Evol ; 40(8)2023 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-37565562

RESUMEN

During the origin of great apes about 14 million years ago, a series of phenotypic innovations emerged, such as the increased body size, the enlarged brain volume, the improved cognitive skill, and the diversified diet. Yet, the genomic basis of these evolutionary changes remains unclear. Utilizing the high-quality genome assemblies of great apes (including human), gibbon, and macaque, we conducted comparative genome analyses and identified 15,885 great ape-specific structural variants (GSSVs), including eight coding GSSVs resulting in the creation of novel proteins (e.g., ACAN and CMYA5). Functional annotations of the GSSV-related genes revealed the enrichment of genes involved in development and morphogenesis, especially neurogenesis and neural network formation, suggesting the potential role of GSSVs in shaping the great ape-shared traits. Further dissection of the brain-related GSSVs shows great ape-specific changes of enhancer activities and gene expression in the brain, involving a group of GSSV-regulated genes (such as NOL3) that potentially contribute to the altered brain development and function in great apes. The presented data highlight the evolutionary role of structural variants in the phenotypic innovations during the origin of the great ape lineage.


Asunto(s)
Hominidae , Animales , Humanos , Hominidae/genética , Evolución Biológica , Genoma , Genómica , Fenotipo
15.
Evol Dev ; 26(5): e12490, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39129398

RESUMEN

Ectothermic vertebrates such as reptiles were assumed to be indeterminate growers, which means that there is no terminal point in time or size for growth in their lifetime. In recent years, evidence for the determinate nature of growth in lizards has accumulated, necessitating a re-examination of models of their ontogeny and evolution of sexual size dimorphism (SSD). In the female-larger gecko Paroedura vazimba, we monitored post-embryonic growth over a period of 15 months. After hatching, females grew faster than males but also reached their final body size, that is, closed growth of their vertebrae, earlier than males. The closure of bone growth in females correlates with the onset of reproductive maturation. We compared this pattern with the previously minutely studied, male-larger species Paroedura picta, where we documented determinate growth as well. We propose a model to explain the evolutionary switches in the direction of SSD in lizards based on bipotential effects of ovarian hormones on growth. In this model, male growth is assumed to require no male-specific growth modifier, such as sex-limited hormonal regulators, while growth is feminized by ovarian hormones in females. Low levels of ovarian hormones can promote bone growth, but high levels associated with maturation of the reproductive organs promote senescence of bone growth plates and thus cessation of bone growth. We suggest that models on growth, life-history and evolution of body size in many lizards should acknowledge their determinate nature of growth.


Asunto(s)
Evolución Biológica , Tamaño Corporal , Lagartos , Caracteres Sexuales , Animales , Lagartos/crecimiento & desarrollo , Lagartos/anatomía & histología , Femenino , Masculino
16.
Development ; 148(5)2021 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-33593818

RESUMEN

Few studies have measured the robustness to perturbations of the final position of a long-range migrating cell. In the nematode Caenorhabditis elegans, the QR neuroblast migrates anteriorly, while undergoing three division rounds. We study the final position of two of its great-granddaughters, the end of migration of which was previously shown to depend on a timing mechanism. We find that the variance in their final position is similar to that of other long-range migrating neurons. As expected from the timing mechanism, the position of QR descendants depends on body size, which we varied by changing maternal age or using body size mutants. Using a mathematical model, we show that body size variation is partially compensated for. Applying environmental perturbations, we find that the variance in final position increased following starvation at hatching. The mean position is displaced upon a temperature shift. Finally, highly significant variation was found among C. elegans wild isolates. Overall, this study reveals that the final position of these neurons is quite robust to stochastic variation, shows some sensitivity to body size and to external perturbations, and varies in the species.This article has an associated 'The people behind the papers' interview.


Asunto(s)
Caenorhabditis elegans/crecimiento & desarrollo , Neuronas/metabolismo , Animales , Tamaño Corporal , Caenorhabditis elegans/metabolismo , Movimiento Celular , Larva/metabolismo , Modelos Teóricos , Neuronas/citología , Procesos Estocásticos , Temperatura
17.
Proc Biol Sci ; 291(2032): 20241498, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39353551

RESUMEN

Body size is a key morphological trait that affects physiology and metabolism, as well as other relevant traits such as fertility and mating success. Some evidence points to a trend of shrinking body size with increasing temperature, but this is far from unequivocal. Here, we assess the evolution of body size under a warming environment in experimentally evolved Drosophila subobscura populations from two distinct geographical origins, tested in both ancestral and warming environments. We observed a decrease in body size in the warming populations, but only in the lower-latitude populations and only when tested in the ancestral (control) environment. The absence of a body size response in the warming environment may be owing to a balance between forces promoting thermodynamic stability-leading to a tendency for body size to decrease-and selection for increased reproductive output-leading to an increase in body size. Our findings indicate that body size variation is complex, with genotype-by-environment interactions occurring. This may explain the lack of consistency across studies. This highlights that predictions of body size evolution under climate warming are not straightforward and emphasizes the need for considering intra- and inter-specific variation in future studies.


Asunto(s)
Evolución Biológica , Tamaño Corporal , Drosophila , Animales , Drosophila/fisiología , Drosophila/anatomía & histología , Temperatura , Femenino , Masculino , Cambio Climático
18.
Proc Biol Sci ; 291(2021): 20232868, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38628132

RESUMEN

Studies of vertebrate bone biomechanics often focus on skeletal adaptations at upper extremes of body mass, disregarding the importance of skeletal adaptations at lower extremes. Yet mammals are ancestrally small and most modern species have masses under 5 kg, so the evolution of morphology and function at small size should be prioritized for understanding how mammals subsist. We examined allometric scaling of lumbar vertebrae in the small-bodied Philippine endemic rodents known as cloud rats, which vary in mass across two orders of magnitude (15.5 g-2700 g). External vertebral dimensions scale with isometry or positive allometry, likely relating to body size and nuances in quadrupedal posture. In contrast to most mammalian trabecular bone studies, bone volume fraction and trabecular thickness scale with positive allometry and isometry, respectively. It is physiologically impossible for these trends to continue to the upper extremes of mammalian body size, and we demonstrate a fundamental difference in trabecular bone allometry between large- and small-bodied mammals. These findings have important implications for the biomechanical capabilities of mammalian bone at small body size; for the selective pressures that govern skeletal evolution in small mammals; and for the way we define 'small' and 'large' in the context of vertebrate skeletons.


Asunto(s)
Vértebras Lumbares , Mamíferos , Ratas , Animales , Mamíferos/fisiología , Huesos , Tamaño Corporal , Vertebrados
19.
Proc Biol Sci ; 291(2024): 20232771, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38864334

RESUMEN

Land use change alters floral resource availability, thereby contributing to declines in important pollinators. However, the severity of land use impact varies by species, influenced by factors such as dispersal ability and resource specialization, both of which can correlate with body size. Here. we test whether floral resource availability in the surrounding landscape (the 'matrix') influences bee species' abundance in isolated remnant woodlands, and whether this effect varies with body size. We sampled quantitative flower-visitation networks within woodland remnants and quantified floral energy resources (nectar and pollen calories) available to each bee species both within the woodland and the matrix. Bee abundance in woodland increased with floral energy resources in the surrounding matrix, with strongest effects on larger-bodied species. Our findings suggest important but size-dependent effects of declining matrix floral resources on the persistence of bees in remnant woodlands, highlighting the need to incorporate landscape-level floral resources in conservation planning for pollinators in threatened natural habitats.


Asunto(s)
Abejas , Tamaño Corporal , Metabolismo Energético , Bosques , Polinización , Densidad de Población , Abejas/anatomía & histología , Abejas/metabolismo , Néctar de las Plantas/metabolismo , Biodiversidad , Animales
20.
Proc Biol Sci ; 291(2029): 20241250, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39166384

RESUMEN

Body size reduction is a universal response to warming, but its ecological consequences across biological levels, from individuals to ecosystems, remain poorly understood. Most biological processes scale with body size, and warming-induced changes in body size can therefore have important ecological consequences. To understand these consequences, we propose a unifying, hierarchical framework for the ecological impacts of intraspecific body size reductions due to thermal plasticity that explicitly builds on three key pathways: morphological constraints, bioenergetic constraints and surface-to-volume ratio. Using this framework, we synthesize key consequences of warming-induced body size reductions at multiple levels of biological organization. We outline how this trait-based framework can improve our understanding, detection and generalization of the ecological impacts of warming.


Asunto(s)
Tamaño Corporal , Ecosistema , Animales , Calentamiento Global , Cambio Climático
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