scholarly journals The relationship between niche breadth and range size of beech ( Fagus ) species worldwide

2021 ◽  
Vol 48 (5) ◽  
pp. 1240-1253
Author(s):  
Qiong Cai ◽  
Erik Welk ◽  
Chengjun Ji ◽  
Wenjing Fang ◽  
Francesco M. Sabatini ◽  
...  
2009 ◽  
Vol 36 (5) ◽  
pp. 854-864 ◽  
Author(s):  
Benjamin Köckemann ◽  
Holger Buschmann ◽  
Christoph Leuschner

Paleobiology ◽  
2020 ◽  
pp. 1-14
Author(s):  
Michelle M. Casey ◽  
Erin E. Saupe ◽  
Bruce S. Lieberman

Abstract Geographic range size and abundance are important determinants of extinction risk in fossil and extant taxa. However, the relationship between these variables and extinction risk has not been tested extensively during evolutionarily “quiescent” times of low extinction and speciation in the fossil record. Here we examine the influence of geographic range size and abundance on extinction risk during the late Paleozoic (Mississippian–Permian), a time of “sluggish” evolution when global rates of origination and extinction were roughly half those of other Paleozoic intervals. Analyses used spatiotemporal occurrences for 164 brachiopod species from the North American midcontinent. We found abundance to be a better predictor of extinction risk than measures of geographic range size. Moreover, species exhibited reductions in abundance before their extinction but did not display contractions in geographic range size. The weak relationship between geographic range size and extinction in this time and place may reflect the relative preponderance of larger-ranged taxa combined with the physiographic conditions of the region that allowed for easy habitat tracking that dampened both extinction and speciation. These conditions led to a prolonged period (19–25 Myr) during which standard macroevolutionary rules did not apply.


2016 ◽  
Vol 46 (3) ◽  
pp. 259-270 ◽  
Author(s):  
Bruno da S. PRUDENTE ◽  
Pedro CARNEIRO-MARINHO ◽  
Roberta de M. VALENTE ◽  
Luciano F. de A. MONTAG

Abstract Studies on feeding ecology of fishes are important to understand the relationship between species and environmental seasonal variations. In tropical rivers, these relationships are mainly modeled by hydrological patterns. Thereby, this study aimed to assess the influence of fluviometric variation and life stage (juveniles and adults) in the feeding ecology of Serrasalmus gouldingi in the lower Anapu River region, located in Eastern Amazon, Pará, Brazil. Specimens were collected bimonthly, considering four different hydrological periods. We assessed the diet composition, feeding intensity and niche breadth of the species. Thirty-two dietary items were identified and grouped into ten categories. A total of 279 stomachs were analyzed, showing a predominance of fish fragments, followed by fruits and seeds. The diet composition of S. gouldingi differed only between drought and flood season, although it did not differ between juveniles and adults. An increase in feeding intensity was recorded during the rise in the water level, with a lower feeding intensity observed during transitional season. Serrasalmus gouldingi showed lower niche breadth during flood season, attributed to the high consumption of fruits and seeds, presenting an omnivorous diet with high tendency towards piscivory. Although less evident than in other Amazon watersheds, the flood pulse in the lower Anapu River region is an important factor influencing the feeding ecology of the species.


Ecography ◽  
2020 ◽  
Vol 43 (5) ◽  
pp. 724-734 ◽  
Author(s):  
Gentile Francesco Ficetola ◽  
Enrico Lunghi ◽  
Raoul Manenti

2019 ◽  
Vol 6 (1) ◽  
pp. 180917 ◽  
Author(s):  
Hideyuki Doi ◽  
Kwang-Hyeon Chang ◽  
Shin-ichi Nakano

Zooplankton species have different feeding habits, but the diversity of their food resources and the factors governing them are still largely unknown. We here estimated the differences in the trophic niche breadths of dominant zooplankton species in ponds, using stable isotopes. To understand the differences in trophic niches of different zooplankton species, we measured the carbon and nitrogen stable isotope ratios and calculated the nearest-neighbour distance (NND), and standard deviation of NND (SDNND) of the bi-plot space of stable carbon and nitrogen isotopes in pond zooplankton. We tested the relationship between the NND/SDNND and environmental factors, as well as the zooplankton biomass, using generalized linear models (GLMs). For cladocerans, including Bosmina, Ceriodaphnia and Daphnia, the NNDs were significantly correlated with the biomass, pond morphology (volume and depth), total phosphorous (TP) and fish presence. For copepod species, including Eodiaptomus and cyclopoids, NNDs were significantly correlated with pond morphology, TP and fish presence, but not with biomass. In GLMs of SDNND, significant correlated factors were less than those for NND, and for some species, pond morphology and TP were significantly correlated with SDNND. Here, we found that the NND and SDNND of zooplankton species were related to various factors, including their biomass, predator presence, pond size and water quality. For cladocerans, biomass may be supported by trophic niche breadth, probably because of the consequences of resource competition. Also, predation and ecosystem size may influence trophic niche breadth due to changes in zooplankton behaviours.


2020 ◽  
Vol 12 (12) ◽  
pp. 2441-2449
Author(s):  
Jennifer James ◽  
Adam Eyre-Walker

Abstract What determines the level of genetic diversity of a species remains one of the enduring problems of population genetics. Because neutral diversity depends upon the product of the effective population size and mutation rate, there is an expectation that diversity should be correlated to measures of census population size. This correlation is often observed for nuclear but not for mitochondrial DNA. Here, we revisit the question of whether mitochondrial DNA sequence diversity is correlated to census population size by compiling the largest data set to date, using 639 mammalian species. In a multiple regression, we find that nucleotide diversity is significantly correlated to both range size and mass-specific metabolic rate, but not a variety of other factors. We also find that a measure of the effective population size, the ratio of nonsynonymous to synonymous diversity, is also significantly negatively correlated to both range size and mass-specific metabolic rate. These results together suggest that species with larger ranges have larger effective population sizes. The slope of the relationship between diversity and range is such that doubling the range increases diversity by 12–20%, providing one of the first quantifications of the relationship between diversity and the census population size.


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