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Biochemistry. Biokhimiia Dec 2022As recently as in 2002 gerontologists widely thought that an aging program that purposely caused aging in mammals was impossible and therefore scientifically ridiculous... (Review)
Review
As recently as in 2002 gerontologists widely thought that an aging program that purposely caused aging in mammals was impossible and therefore scientifically ridiculous because it violated widely accepted concepts regarding the nature of the evolution process. However, a number of modern evolutionary mechanics concepts such as group selection and evolvability suggest that an individually adverse trait like aging can evolve if it creates an advantage (reduced probability of extinction) for a population. Genetics discoveries suggest that aging creates multiple population advantages and, therefore, aging programs that purposely cause and regulate aging evolved in mammals. This led to various concepts regarding the nature of the program. One such concept is that aging is a completely genetically specified function of age, essentially a biological clock. However, this article presents evidence and theoretical basis for the idea that the programmed aging function is controlled by an adaptive mechanism that can sense local or temporary conditions that affect the optimum aging function and adjust it to compensate for those conditions. This issue is important for medical research because the sensing mechanisms and associated signaling provide additional points at which intervention in the aging process and associated highly age-related diseases could be attempted.
Topics: Animals; Biological Evolution; Aging; Phenotype; Mammals; Biological Clocks
PubMed: 36717437
DOI: 10.1134/S000629792212001X -
Plant Biology (Stuttgart, Germany) Oct 2023Pollinator shifts are often related to speciation in angiosperms, and the relationship between them has been discussed in several plant taxa. Although limited... (Review)
Review
Pollinator shifts are often related to speciation in angiosperms, and the relationship between them has been discussed in several plant taxa. Although limited information on plants pollinated by non-flying mammals in Central and South America and Africa is available, related research has not been conducted in Asia. Herein, I summarize the available knowledge of pollination in Asian Mucuna (Fabaceae), a genus mainly distributed in the tropics, and discuss the evolution of plants pollinated by non-flying mammals in Asia. Nineteen pollinator species have been recorded and pollination systems have been categorized into four types. An examination of the relationship between Mucuna species and their pollinators from the lineage perspective revealed that all species in Mucuna, subgenus Macrocarpa, which are distributed in Asia, are pollinated exclusively by non-flying mammals. Additionally, plants pollinated by non-flying mammals were found to have diverged from bat-pollinated and non-flying mammal-pollinated plants, while plants pollinated by non-flying mammals have evolved multiple times. This is a unique example of evolutionary transition. I hypothesize that the diversification of squirrel species in tropical Asia may have led to the speciation and diversification of Mucuna in Asia. Furthermore, the behavioural and ecological characteristics of bats and birds in Asia differ from the characteristics of those in other regions, implying that Asian Mucuna species do not rely on bat or bird pollinators. The adaptation of floral characteristics to pollinators is not well understood in Asia. Mammal-pollinated plants in Asia may have evolved differently from those in other regions and have unique pollination systems.
Topics: Animals; Pollination; Fabaceae; Mucuna; Chiroptera; Flowers; Mammals; Plants
PubMed: 37408380
DOI: 10.1111/plb.13557 -
The Veterinary Clinics of North... May 2024Pediatric exotic companion animal nutrition is a broad topic, spanning small mammals, reptiles, and birds. Little research has been performed focusing on the juvenile... (Review)
Review
Pediatric exotic companion animal nutrition is a broad topic, spanning small mammals, reptiles, and birds. Little research has been performed focusing on the juvenile life stages of these species because they are largely acquired by clients at the young adult stage. The information that does exist has been compiled by wildlife rehabilitators, commercial breeders, and/or exotic captive breeding programs, such as those that exist in zoologic facilities. In this article, we discuss natural history, feeding strategies, energy requirements, digestive physiology and diet digestibility, and key nutrients of concern as factors for determining an appropriate diet for pediatric exotic species.
Topics: Humans; Animals; Pets; Animals, Exotic; Animals, Wild; Reptiles; Mammals
PubMed: 38030515
DOI: 10.1016/j.cvex.2023.11.016 -
PeerJ 2024The mammalian crown originated during the Mesozoic and subsequently radiated into the substantial array of forms now extant. However, for about 100 million years before...
The mammalian crown originated during the Mesozoic and subsequently radiated into the substantial array of forms now extant. However, for about 100 million years before the crown's origin, a diverse array of stem mammalian lineages dominated terrestrial ecosystems. Several of these stem lineages overlapped temporally and geographically with the crown mammals during the Mesozoic, but by the end of the Cretaceous crown mammals make up the overwhelming majority of the fossil record. The progress of this transition between ecosystems dominated by stem mammals and those dominated by crown mammals is not entirely clear, in part due to a distinct separation of analyses and datasets. Analyses of macroevolutionary patterns tend to focus on either the Mammaliaformes or the non-mammalian cynodonts, with little overlap in the datasets, preventing direct comparison of the diversification trends. Here I analyse species richness and biogeography of Synapsida as a whole during the Mesozoic, allowing comparison of the patterns in the mammalian crown and stem within a single framework. The analysis reveals the decline of the stem mammals occurred in two discrete phases. The first phase occurred between the Triassic and Middle Jurassic, during which the stem mammals were more restricted in their geographic range than the crown mammals, although within localities their species richness remained at levels seen previously. The second phase was a decline in species richness, which occurred during the Lower Cretaceous. The results show the decline of stem mammals, including tritylodontids and several mammaliaform groups, was not tied to a specific event, nor a gradual decline, but was instead a multiphase transition.
Topics: Animals; Ecosystem; Fossils; Mammals
PubMed: 38436024
DOI: 10.7717/peerj.17004 -
Proceedings of the National Academy of... Mar 2023Wild mammals are icons of conservation efforts, yet there is no rigorous estimate available for their overall global biomass. Biomass as a metric allows us to compare...
Wild mammals are icons of conservation efforts, yet there is no rigorous estimate available for their overall global biomass. Biomass as a metric allows us to compare species with very different body sizes, and can serve as an indicator of wild mammal presence, trends, and impacts, on a global scale. Here, we compiled estimates of the total abundance (i.e., the number of individuals) of several hundred mammal species from the available data, and used these to build a model that infers the total biomass of terrestrial mammal species for which the global abundance is unknown. We present a detailed assessment, arriving at a total wet biomass of ≈20 million tonnes (Mt) for all terrestrial wild mammals (95% CI 13-38 Mt), i.e., ≈3 kg per person on earth. The primary contributors to the biomass of wild land mammals are large herbivores such as the white-tailed deer, wild boar, and African elephant. We find that even-hoofed mammals (artiodactyls, such as deer and boars) represent about half of the combined mass of terrestrial wild mammals. In addition, we estimated the total biomass of wild marine mammals at ≈40 Mt (95% CI 20-80 Mt), with baleen whales comprising more than half of this mass. In order to put wild mammal biomass into perspective, we additionally estimate the biomass of the remaining members of the class Mammalia. The total mammal biomass is overwhelmingly dominated by livestock (≈630 Mt) and humans (≈390 Mt). This work is a provisional census of wild mammal biomass on Earth and can serve as a benchmark for human impacts.
Topics: Humans; Animals; Swine; Deer; Biomass; Cetacea; Caniformia; Sus scrofa
PubMed: 36848563
DOI: 10.1073/pnas.2204892120 -
Ecology Mar 2023Anthropogenic activities since the European colonization of the North American Great Plains have drastically altered landscape composition and configuration,...
Anthropogenic activities since the European colonization of the North American Great Plains have drastically altered landscape composition and configuration, subsequently affecting native biodiversity. These contemporary human-modified landscapes may affect mammal species' distributions, diel activity patterns, habitat use, and interspecific interactions, though a better understanding of these effects on mammals occurring in remaining prairie landscapes is needed. To fill this gap, we surveyed 381 randomly selected sites in 2018, 2019, and 2020 using motion-sensing camera traps across the western part of the US state of Kansas (7,160,077 ha). Sites were separated by ≥2 km ( = 8.16 km, SD = 3.61), and cameras were secured to a metal post 40 cm above ground and randomly oriented toward the north or south. We placed an olfactory attractant (mixture of skunk essence and petroleum jelly) on a wooden stake 3 m in front of each camera. Cameras were in place at each site for 28 consecutive days for each year. We manually identified all mammal species detected at each site, collating these data into a database that included taxonomic information for 14 families of mammals (Antilocapridae, Bovidae, Canidae, Cervidae, Cricetidae, Dasypodidae, Didelphidae, Erethizontidae, Felidae, Heteromyidae, Leporidae, Mephitidae, Mustelidae, Procyonidae, Sciuridae, and Muridae) comprising 28 total species. We recorded 31,178 mammal photographs (nonindependent events) over 27,954 camera trap nights during 2018 (n = 10,351), 2019 (n = 9478), and 2020 (n = 8125). Additionally, we included the time and date of each photocapture. Moreover, we gathered survey-specific data useful for modeling species-specific detection along with site-level habitat composition data taken at each site each year. These data will be useful for examining habitat use, species distributions, diel activity patterns, and spatiotemporal interactions between species and across guilds of mammals occurring in a rapidly changing agro-prairie ecosystem. There are no copyright restrictions, but we ask researchers to cite this paper when using these data for publication.
Topics: Animals; Humans; Ecosystem; Grassland; Biodiversity; Mammals; Deer; Sciuridae
PubMed: 36478344
DOI: 10.1002/ecy.3945 -
PloS One 2022Detailed knowledge about biodiversity distribution is critical for monitoring the biological effects of global change processes. Biodiversity knowledge gaps hamper the...
Detailed knowledge about biodiversity distribution is critical for monitoring the biological effects of global change processes. Biodiversity knowledge gaps hamper the monitoring of conservation trends and they are especially evident in the desert biome. Mauritania constitutes a remarkable example on how remoteness and regional insecurity affect current knowledge gaps. Mammals remain one of the least studied groups in this country, without a concerted species checklist, the mapping of regions concentrating mammal diversity, or a national assessment of their conservation status. This work assessed the diversity, distribution, and conservation of land mammals in Mauritania. A total of 6,718 published and original observations were assembled in a spatial database and used to update the occurrence status, distribution area, and conservation status. The updated taxonomic list comprises 107 species, including 93 extant, 12 Regionally Extinct, and 2 Extinct in the Wild. Mapping of species distributions allowed locating concentrations of extant mammal species richness in coastal areas, along the Senegal River valley, and in mountain plateaus. Recent regional extinction of large-sized Artiodactyla and Carnivora has been very high (11% extinct species). From the extant mammals, 11% are threatened, including flagship species (e.g., Addax nasomaculatus and Panthera pardus). Species richness is poorly represented by the current protected areas. Despite the strong advances made, 23% of species categorise as Data Deficient. Persisting systematics and distribution uncertainties require further research. Field surveys in currently unexplored areas (northern and south-eastern regions) are urgently needed to increase knowledge about threatened mammals. The long-term conservation of land mammals in Mauritania is embedded in a complex web of socioeconomic and environmental factors that call for collaborative action and investment in sustainable human development. The current work sets the baseline for the future development of detailed research studies and to address the general challenges faced by mammals and biodiversity in the country.
Topics: Africa, Western; Animals; Biodiversity; Conservation of Natural Resources; Humans; Mammals; Mauritania
PubMed: 35913972
DOI: 10.1371/journal.pone.0269870 -
Annual Review of Animal Biosciences Feb 2021The genomes of placental mammals are being sequenced at an unprecedented rate. Alignments of hundreds, and one day thousands, of genomes spanning the rich living and... (Review)
Review
The genomes of placental mammals are being sequenced at an unprecedented rate. Alignments of hundreds, and one day thousands, of genomes spanning the rich living and extinct diversity of species offer unparalleled power to resolve phylogenetic controversies, identify genomic innovations of adaptation, and dissect the genetic architecture of reproductive isolation. We highlight outstanding questions about the earliest phases of placental mammal diversification and the promise of newer methods, as well as remaining challenges, toward using whole genome data to resolve placental mammal phylogeny. The next phase of mammalian comparative genomics will see the completion and application of finished-quality, gapless genome assemblies from many ordinal lineages and closely related species. Interspecific comparisons between the most hypervariable genomic loci will likely reveal large, but heretofore mostly underappreciated, effects on population divergence, morphological innovation, and the origin of new species.
Topics: Adaptation, Biological; Animals; Biological Evolution; Eutheria; Genetic Speciation; Genomics; Phylogeny
PubMed: 33228377
DOI: 10.1146/annurev-animal-061220-023149 -
Gene Jan 2022Gut microbiome influence the health and evolution of mammals and multiple factors modulate the structure and function of gut microbiome. However, the specific changes of...
Gut microbiome influence the health and evolution of mammals and multiple factors modulate the structure and function of gut microbiome. However, the specific changes of the diets and phylogeny on the gut microbiome were unclear. Here, we compared the gut microbiome of 16 rare wild mammals. All data (>200G 16S rRNA gene sequences) were generated using a high-throughput sequencing platform. Firmicutes and Bacteroidetes were the most predominant phyla in all mammals. However, Proteobacteria was an additionally dominant phylum specifically detected in the microbiome of carnivores and omnivores. Moreover, the dominant phyla in canids were Firmicutes, Bacteroidetes, Proteobacteria, and Fusobacteria. Phylogenetic reconstructions based on the gut microbiome and mitochondrial genome of these mammals were similar. The impact of the host on the microbiome community composition was most evident when considering conspecific and congeneric relationships. Similarity clustering showed that the gut microbiome of herbivores was clustered together, and the other clade comprised both omnivores and carnivores. Collectively, these results revealed that phylogenetic relationships and diet have an important impact on the gut microbiome, and thus the gut microbiome community composition may reflect both the phylogenetic relationships and diets. This study provides valuable basic data to facilitate future efforts related to animal conservation and health.
Topics: Animals; Animals, Wild; Bacteria; Biological Evolution; Carnivory; Diet; Evolution, Molecular; Feces; Feeding Behavior; Gastrointestinal Microbiome; Herbivory; High-Throughput Nucleotide Sequencing; Mammals; Microbiota; Phylogeny; RNA, Ribosomal, 16S
PubMed: 34627942
DOI: 10.1016/j.gene.2021.145999 -
Anatomical Record (Hoboken, N.J. : 2007) Mar 2022Marine mammals are a unique group of organisms that are secondarily adapted to the aquatic environment. Their specific lifestyle requires numerous adaptations of anatomy...
Marine mammals are a unique group of organisms that are secondarily adapted to the aquatic environment. Their specific lifestyle requires numerous adaptations of anatomy and physiology in general, and sensory physiology in particular. During the course of evolution, marine mammal senses changed to fit with the specific requirements of underwater sensing, while at the same time retaining aerial sensing to various degrees. In this special issue, state of the art science in the field of marine mammal sensory research is reported for representatives of all marine mammal groups, unfortunately with the exclusion of the polar bear. The articles focus on somatosensation of the glabrous skin of cetaceans and mechanoreception, including haptics, hydrodynamics, and acoustics, to chemoreception. Articles even deal with electroreception, highlighting that the bottlenose dolphin can perceive weak electric stimuli, and vision, indicating that harbor seals are able to derive temporal information from an optical stimulus. Altogether this special issue illustrates the diversity of research in the field regarding sensory systems, species, or experimental approaches. The strength of this special issue lies in the combination of carefully conducted anatomical studies paired with observations and behavioral studies attempting to relate "form" and "function" as well as in the many impulses and future avenues mentioned by numerous contributions.
Topics: Adaptation, Physiological; Animals; Caniformia; Cetacea; Mammals; Sense Organs
PubMed: 35077022
DOI: 10.1002/ar.24865