Of mice and wrens: the relation between abundance and geographic range size in British mammals and birds

We examine the relation between population size and geographic range size for British breeding birds and mammals. As for most other assemblages studied, a strong positive interspecific correlation is found in both taxa. The relation is also recovered once the phylogenetic relatedness of species has been controlled for using an evolutionary comparative method. The slope of the relation is steeper for birds than for mammals, but this is due in large part to two species of mammals that have much higher population sizes than expected from their small geographic ranges. These outlying mammal species are the only ones in Britain to be found only on small offshore islands, and so may be exhibiting density compensation effects. With them excluded, the slope of the abundance–range size relation for mammals is not significantly different to that for birds. However, the elevation of the relation is higher for mammals than for birds, indicating that mammals are approximately 30 times more abundant than birds of equivalent geographic range size. An earlier study of these assemblages showed that, for a given body mass, bats had abundances more similar to birds than to non–volant mammals, suggesting that the difference in abundance between mammals and birds might be due to constraints of flight. Our analyses show that the abundance–range size relation for bats is not different for that from other mammals, and that the anomalously low abundance of bats for their body mass may result because they have smaller than expected geographic extents for their size. Other reasons why birds and mammals might have different elevations for the relation between population size and geographic range size are discussed, together with possible reasons for why the slopes of these relations might be similar.

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Genome size versus geographic range size in birds

PeerJ ◽

10.7717/peerj.10868 ◽

2021 ◽

Vol 9 ◽

pp. e10868

Author(s):

Beata Grzywacz ◽

Piotr Skórka

Keyword(s):

Natural Selection ◽

Chromosome Number ◽

Genome Size ◽

Body Mass ◽

Generalized Least Squares ◽

Geographic Range ◽

Range Size ◽

Geographic Ranges ◽

Brain Mass ◽

Terrestrial Vertebrates

Why do some species occur in small, restricted areas, while others are distributed globally? Environmental heterogeneity increases with area and so does the number of species. Hence, diverse biotic and abiotic conditions across large ranges may lead to specific adaptations that are often linked to a species’ genome size and chromosome number. Therefore, a positive association between genome size and geographic range is anticipated. Moreover, high cognitive ability in organisms would be favored by natural selection to cope with the dynamic conditions within large geographic ranges. Here, we tested these hypotheses in birds—the most mobile terrestrial vertebrates—and accounted for the effects of various confounding variables, such as body mass, relative brain mass, and geographic latitude. Using phylogenetic generalized least squares and phylogenetic confirmatory path analysis, we demonstrated that range size is positively associated with bird genome size but probably not with chromosome number. Moreover, relative brain mass had no effect on range size, whereas body mass had a possible weak and negative effect, and range size was larger at higher geographic latitudes. However, our models did not fully explain the overall variation in range size. Hence, natural selection may impose larger genomes in birds with larger geographic ranges, although there may be additional explanations for this phenomenon.

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Geographic range size is predicted by plant mating system

10.1101/013417 ◽

2015 ◽

Author(s):

Dena Grossenbacher ◽

Ryan Briscoe Runquist ◽

Emma Goldberg ◽

Yaniv Brandvain

Keyword(s):

Geographic Range ◽

Range Size ◽

Geographic Ranges ◽

Biological Trait ◽

Geographic Range Size ◽

Self Fertilization ◽

Mate Limitation ◽

Close Relatives ◽

Annual Life History ◽

Plant Mating System

Species' geographic ranges vary enormously, and even closest relatives may differ in range size by several orders of magnitude. With data from hundreds of species spanning 20 genera in 15 families, we show that plant species that autonomously reproduce via self-pollination consistently have larger geographic ranges than their close relatives that generally require two parents for reproduction. Further analyses strongly implicate autonomous self-fertilization in causing this relationship, as it is not driven by traits such as polyploidy or annual life history whose evolution is sometimes correlated with autonomous self-fertilization. Furthermore, we find that selfers occur at higher maximum latitudes and that disparity in range size between selfers and outcrossers increases with time since their separation. Together, these results show that autonomous reproduction - a critical biological trait that eliminates mate limitation and thus potentially increases the probability of establishment - increases range size.

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Global Scale Macroecology: Interactions between Population Size, Geographic Range Size and Body Size in the Anseriformes

Journal of Animal Ecology ◽

10.2307/5669 ◽

1996 ◽

Vol 65 (6) ◽

pp. 701 ◽

Cited By ~ 131

Author(s):

Kevin J. Gaston ◽

Tim M. Blackburn

Keyword(s):

Body Size ◽

Population Size ◽

Global Scale ◽

Geographic Range ◽

Range Size ◽

Geographic Range Size

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Occupancy, range size, and phylogeny in Eurasian Pliocene to Recent large mammals

Paleobiology ◽

10.1666/09059.1 ◽

2010 ◽

Vol 36 (3) ◽

pp. 399-414 ◽

Cited By ~ 34

Author(s):

Francesco Carotenuto ◽

Carmela Barbera ◽

Pasquale Raia

Keyword(s):

Body Size ◽

Evolutionary Ecology ◽

Phylogenetic Signal ◽

Geographic Range ◽

Range Size ◽

Mammal Species ◽

Mean Values ◽

Geographic Range Size ◽

Western Eurasia ◽

Species Occupancy

Temporal patterns in species occupancy and geographic range size are a major topic in evolutionary ecology research. Here we investigate these patterns in Pliocene to Recent large mammal species and genera in Western Eurasia. By using an extensively sampled fossil record including some 700 fossil localities, we found occupancy and range size trajectories over time to be predominantly peaked among both species and genera, meaning that occupancy and range size reached their maxima midway along taxon existence. These metrics are strongly correlated with each other and to body size, after phylogeny is accounted for by using two different phylogenetic topologies for both species and genera. Phylogenetic signal is strong in body size, and weaker but significant in both occupancy and range size mean values among genera, indicating that these variables are heritable. The intensity of phylogenetic signal is much weaker and often not significant at the species level. This suggests that within genera, occupancy and range size are somewhat variable. However, sister taxa inherit geographic position (the center of their geographic distribution). Taken together, the latter two results indicate that sister species occupy similar positions on the earth's surface, and that the expansion of the geographic range during the existence of a given genus is driven by range expansion of one or more of the species it includes, rather than simply being the summation of these species ranges.

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Phylogenetic heritability of geographic range size in haematophagous ectoparasites: time of divergence and variation among continents

Parasitology ◽

10.1017/s0031182018000550 ◽

2018 ◽

Vol 145 (12) ◽

pp. 1623-1632

Author(s):

Boris R. Krasnov ◽

Georgy I. Shenbrot ◽

Luther van der Mescht ◽

Elizabeth M. Warburton ◽

Irina S. Khokhlova

Keyword(s):

Geographic Variation ◽

Southern Africa ◽

Phylogenetic Signal ◽

Geographic Range ◽

Range Size ◽

Geographic Ranges ◽

Geographic Range Size ◽

Northern Regions ◽

Time Of Divergence ◽

Over Time

AbstractTo understand existence, patterns and mechanisms behind phylogenetic heritability in the geographic range size (GRS) of parasites, we measured phylogenetic signal (PS) in the sizes of both regional (within a region) and continental (within a continent) geographic ranges of fleas in five regions. We asked whether (a) GRS is phylogenetically heritable and (b) the manifestation of PS varies between regions. We also asked whether geographic variation in PS reflects the effects of the environment's spatiotemporal stability (e.g. glaciation disrupting geographic ranges) or is associated with time since divergence (accumulation differences among species over time). Support for the former hypothesis would be indicated by stronger PS in southern than in northern regions, whereas support for the latter hypothesis would be shown by stronger PS in regions with a large proportion of species belonging to the derived lineages than in regions with a large proportion of species belonging to the basal lineages. We detected significant PS in both regional and continental GRSs of fleas from Canada and in continental GRS of fleas from Mongolia. No PS was found in the GRS of fleas from Australia and Southern Africa. Venezuelan fleas demonstrated significant PS in regional GRS only. Local Indicators of Phylogenetic Association detected significant local positive autocorrelations of GRS in some clades even in regions in which PS has not been detected across the entire phylogeny. This was mainly characteristic of younger taxa.

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Comparing Genetic Diversity in Three Threatened Oaks

Forests ◽

10.3390/f12050561 ◽

2021 ◽

Vol 12 (5) ◽

pp. 561

Author(s):

Emma Suzuki Spence ◽

Jeremie B. Fant ◽

Oliver Gailing ◽

M. Patrick Griffith ◽

Kayri Havens ◽

...

Keyword(s):

Genetic Diversity ◽

Population Size ◽

Rare Species ◽

Genetic Erosion ◽

Geographic Range ◽

Range Size ◽

Ex Situ ◽

Botanic Gardens ◽

Geographic Range Size

Genetic diversity is a critical resource for species’ survival during times of environmental change. Conserving and sustainably managing genetic diversity requires understanding the distribution and amount of genetic diversity (in situ and ex situ) across multiple species. This paper focuses on three emblematic and IUCN Red List threatened oaks (Quercus, Fagaceae), a highly speciose tree genus that contains numerous rare species and poses challenges for ex situ conservation. We compare the genetic diversity of three rare oak species—Quercus georgiana, Q. oglethorpensis, and Q. boyntonii—to common oaks; investigate the correlation of range size, population size, and the abiotic environment with genetic diversity within and among populations in situ; and test how well genetic diversity preserved in botanic gardens correlates with geographic range size. Our main findings are: (1) these three rare species generally have lower genetic diversity than more abundant oaks; (2) in some cases, small population size and geographic range correlate with genetic diversity and differentiation; and (3) genetic diversity currently protected in botanic gardens is inadequately predicted by geographic range size and number of samples preserved, suggesting non-random sampling of populations for conservation collections. Our results highlight that most populations of these three rare oaks have managed to avoid severe genetic erosion, but their small size will likely necessitate genetic management going forward.

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Environmental controls on geographic range size in marine animal genera

Paleobiology ◽

10.1666/13056 ◽

2014 ◽

Vol 40 (3) ◽

pp. 440-458 ◽

Cited By ~ 23

Author(s):

Michael Foote

Keyword(s):

Sampling Bias ◽

Geographic Range ◽

Depositional Environments ◽

Range Size ◽

Marine Animal ◽

Geographic Ranges ◽

Environmental Controls ◽

Occurrence Data ◽

Environmental Preference ◽

Geographic Range Size

Here I test the hypothesis that temporal variation in geographic range size within genera is affected by the expansion and contraction of their preferred environments. Using occurrence data from the Paleobiology Database, I identify genera that have a significant affinity for carbonate or terrigenous clastic depositional environments that transcends the Database's representation of these environments during the stratigraphic range of each genus. These affinity assignments are not a matter of arbitrarily subdividing a continuum in preference; rather, genera form distinct, nonrandom subsets with respect to environmental preference. I tabulate the stage-by-stage transitions in range size within individual genera and the stage-by-stage changes in the extent of each environment. Comparing the two shows that genera with a preference for a given environment are more likely to increase in geographic range, and to show a larger average increase in range, when that environment increases in areal extent, and likewise for decreases in geographic range and environmental area. Similar results obtain for genera with preferences for reefal and non-reef settings. Simulations and subsampling experiments suggest that these results are not artifacts of methodology or sampling bias. Nor are they confined to particular higher taxa. Genera with roughly equal preference for carbonates and clastics do not have substantially broader geographic ranges than those with a distinct affinity, suggesting that, at this scale of analysis, spatial extent of preferred environment outweighs breadth of environmental preference in governing geographic range. These results pertain to changes over actual geologic time within individual genera, not overall average ranges. Recent work has documented a regular expansion and contraction when absolute time is ignored and genera are superimposed to form a composite average. Environmental preference may contribute to this pattern, but its role appears to be minor, limited mainly to the initial expansion and final contraction of relatively short-lived genera.

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