Environmental and ecological factors mediate taxonomic composition and body size of polyplacophoran assemblages along the Peruvian Province

Abstract Intertidal communities’ composition and diversity usually exhibit strong changes in relation to environmental gradients at different biogeographical scales. This study represents the first comprehensive diversity and composition description of polyplacophoran assemblages along the Peruvian Province (SE Pacific, 12°S–39°S), as a model system for ecological latitudinal gradients. A total of 4,775 chitons from 21 species were collected on twelve localities along the Peruvian Province. This sampling allowed us to quantitatively estimate the relative abundance of the species in this assemblage, and to test whether chitons conform to elementary predictions of major biogeographic patterns such as a latitudinal diversity gradient. We found that the species composition supported the division of the province into three ecoregional faunal groups (i.e. Humboldtian, Central Chile, and Araucanian). Though chiton diversity did not follow a clear latitudinal gradient, changes in species composition were dominated by smaller scale variability in salinity and temperature. Body size significantly differed by ecoregions and species, indicating latitudinal size-structure assamblages. In some localities body size ratios differed from a random assemblage, evidencing competition at local scale. Changes in composition between ecoregions influence body size structure, and their overlapping produce vertical size segregation, suggesting that competition coupled with environmental conditions structure these assemblages.

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Comparison of fecundity-length-latitude relationships between nonanadromous (kokanee) and anadromous sockeye salmon (Oncorhynchus nerka)

Canadian Journal of Zoology ◽

10.1139/z00-106 ◽

2000 ◽

Vol 78 (10) ◽

pp. 1791-1805 ◽

Cited By ~ 15

Author(s):

M D McGurk

Keyword(s):

Body Size ◽

Egg Size ◽

Sockeye Salmon ◽

Environmental Gradients ◽

Oncorhynchus Nerka ◽

Latitudinal Gradients ◽

Egg Number ◽

Latitudinal Clines ◽

Regression Slopes ◽

Highly Correlated

This study compared fecundity-length-latitude relationships between 25 kokanee populations (15 natural and 10 introduced) and 48 sockeye salmon populations. Significant differences confirmed the hypothesis that the two Oncorhynchus nerka variants follow different reproductive strategies: (i) fecundity is more highly correlated with length for kokanee than for sockeye salmon; (ii) kokanee have higher fecundity-length regression slopes and lower intercepts than sockeye salmon; (iii) kokanee populations share a common fecundity-length regression slope, but sockeye salmon populations do not; and (iv) average lengths and fecundities of kokanee decrease with increasing latitude, but those of sockeye salmon do not. The first three findings confirm that kokanee maintain a constant egg size while increasing egg number with increasing body size but that sockeye salmon increase both egg number and egg size with increasing body size. Kokanee egg sizes may be less variable than those of sockeye salmon because kokanee have lower and less variable energetic costs of spawning migration and tend to use spawning gravel with smaller and less variable particle sizes. Latitudinal clines in kokanee length and fecundity may reflect latitudinal gradients in temperature and duration of the growing season. Such environmental gradients may explain why kokanee populations are rarely found as far north as Alaska.

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Climate change and body size shift in Mediterranean bivalve assemblages: unexpected role of biological invasions

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2017.0357 ◽

2017 ◽

Vol 284 (1860) ◽

pp. 20170357 ◽

Cited By ~ 5

Author(s):

Rafał Nawrot ◽

Paolo G. Albano ◽

Devapriya Chattopadhyay ◽

Martin Zuschin

Keyword(s):

Climate Change ◽

Body Size ◽

Alien Species ◽

Mediterranean Sea ◽

Red Sea ◽

Size Structure ◽

Functional Trait ◽

Taxonomic Composition ◽

Species Invasions ◽

The Mediterranean

Body size is a synthetic functional trait determining many key ecosystem properties. Reduction in average body size has been suggested as one of the universal responses to global warming in aquatic ecosystems. Climate change, however, coincides with human-enhanced dispersal of alien species and can facilitate their establishment. We address effects of species introductions on the size structure of recipient communities using data on Red Sea bivalves entering the Mediterranean Sea through the Suez Canal. We show that the invasion leads to increase in median body size of the Mediterranean assemblage. Alien species are significantly larger than native Mediterranean bivalves, even though they represent a random subset of the Red Sea species with respect to body size. The observed patterns result primarily from the differences in the taxonomic composition and body-size distributions of the source and recipient species pools. In contrast to the expectations based on the general temperature–size relationships in marine ectotherms, continued warming of the Mediterranean Sea indirectly leads to an increase in the proportion of large-bodied species in bivalve assemblages by accelerating the entry and spread of tropical aliens. These results underscore complex interactions between changing climate and species invasions in driving functional shifts in marine ecosystems.

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Rapid diversification and not clade age explains high diversity in neotropical Adelpha butterflies

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2010.2140 ◽

2010 ◽

Vol 278 (1713) ◽

pp. 1777-1785 ◽

Cited By ~ 42

Author(s):

Sean P. Mullen ◽

Wesley K. Savage ◽

Niklas Wahlberg ◽

Keith R. Willmott

Keyword(s):

Species Richness ◽

Host Plant ◽

Diversification Rate ◽

Latitudinal Gradients ◽

Adaptive Divergence ◽

Biogeographic Patterns ◽

Diversity Gradient ◽

Larval Host ◽

Alternative Hypotheses ◽

Close Relatives

Latitudinal gradients in species richness are among the most well-known biogeographic patterns in nature, and yet there remains much debate and little consensus over the ecological and evolutionary causes of these gradients. Here, we evaluated whether two prominent alternative hypotheses (namely differences in diversification rate or clade age) could account for the latitudinal diversity gradient in one of the most speciose neotropical butterfly genera ( Adelpha ) and its close relatives. We generated a multilocus phylogeny of a diverse group of butterflies in the containing tribe Limenitidini, which has both temperate and tropical representatives. Our results suggest there is no relationship between clade age and species richness that could account for the diversity gradient, but that instead it could be explained by a significantly higher diversification rate within the predominantly tropical genus Adelpha . An apparent early larval host-plant shift to Rubiaceae and other plant families suggests that the availability of new potential host plants probably contributed to an increase in diversification of Adelpha in the lowland Neotropics. Collectively, our results support the hypothesis that the equatorial peak in species richness observed within Adelpha is the result of increased diversification rate in the last 10–15 Myr rather than a function of clade age, perhaps reflecting adaptive divergence in response to the dramatic host-plant diversity found within neotropical ecosystems.

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Mechanistic macroecology: exploring the drivers of latitudinal variation in terrestrial body size in a General Ecosystem Model

10.1101/775957 ◽

2019 ◽

Author(s):

Michael Brian James Harfoot ◽

Andrew Abraham ◽

Derek P Tittensor ◽

Gabriel C Costa ◽

Søren Faurby ◽

...

Keyword(s):

Body Size ◽

Body Mass ◽

Resource Availability ◽

Large Scale ◽

Environmental Gradients ◽

Ecosystem Model ◽

Experimental Manipulation ◽

Statistical Correlation ◽

Biogeographic Patterns ◽

Empirical Estimates

ABSTRACTMany mechanisms have been hypothesized to explain Bergmann’s rule - the correlation of body size with latitude. However, it is not feasible to assess the contribution of hypothesised mechanisms by experimental manipulation or statistical correlation. Here, we evaluate two of the principal hypothesised mechanisms, related to thermoregulation and resource availability, using structured experiments in a mechanistic global ecosystem model. We simulated the broad structure of assemblages and ecosystems using the Madingley model, a mechanistic General Ecosystem Model (GEM). We compared emergent modelled biogeographic patterns in body mass to empirical patterns for mammals and birds. We then explored the relative contribution of thermoregulation and resource availability to body mass clines by manipulating the model’s environmental gradients. Madingley produces body size gradients that are in broad agreement with empirical estimates. Thermoregulation and resource availability were both important controls on body mass for endotherms, but only temperature for ectotherms. Our results suggest that seasonality explains animal body mass patterns through a complex set of mechanisms. Process-based GEMs generate broadly realistic biogeographic body mass patterns. Ecologists can use them in novel ways: to explore causality, or for generating and testing hypotheses for large-scale, emergent ecological patterns. At the same time, macroecological patterns are useful for evaluating mechanistic models. Iteratively developing GEMs, and evaluating them against macroecological patterns, could generate new insights into the complex causes of such patterns.

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Concordance of taxonomic composition patterns across multiple lake assemblages: effects of scale, body size, and land use

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f99-139 ◽

1999 ◽

Vol 56 (11) ◽

pp. 2029-2040 ◽

Cited By ~ 75

Author(s):

Andrew P Allen ◽

Thomas R Whittier ◽

David P Larsen ◽

Philip R Kaufmann ◽

Raymond J O'Connor ◽

...

Keyword(s):

Land Use ◽

Body Size ◽

Environmental Gradient ◽

Environmental Gradients ◽

Taxonomic Composition ◽

Forest Composition ◽

Benthic Macroinvertebrate ◽

Close Correspondence ◽

Lake Productivity ◽

Effects Of Land Use

We assessed environmental gradients and the extent to which they induced concordant patterns of taxonomic composition among benthic macroinvertebrate, riparian bird, sedimentary diatom, fish, and pelagic zooplankton assemblages in 186 northeastern U.S.A. lakes. Human population density showed a close correspondence to this region's dominant environmental gradient. This reflected the constraints imposed by climate and geomorphology on land use and, in turn, the effects of land use on the environment (e.g., increasing lake productivity). For the region as a whole, concordance was highest among assemblages whose taxa were relatively similar in body size. The larger-bodied assemblages (benthos, birds, fish) were correlated most strongly with factors of broader scale (climate, forest composition) than the diatoms and zooplankton (pH, lake depth). Assemblage concordance showed little or no relationship to body size when upland and lowland subregions were examined separately. This was presumably because differences in the scales at which each assemblage integrated the environment were obscured more locally. The larger-bodied assemblages showed stronger associations with land use than the diatoms and zooplankton. This occurred, in part, because they responded more strongly to broad-scale, nonanthropogenic factors that also affected land use. We argue, however, that the larger-bodied assemblages have also been more severely affected by human activities.

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Mammalian body size is determined by interactions between climate, urbanization, and ecological traits

Communications Biology ◽

10.1038/s42003-021-02505-3 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Maggie M. Hantak ◽

Bryan S. McLean ◽

Daijiang Li ◽

Robert P. Guralnick

Keyword(s):

Body Size ◽

Resource Availability ◽

Critical Role ◽

Size Variation ◽

Ecological Factors ◽

Species Traits ◽

Body Size Variation ◽

Resource Availability Hypothesis ◽

Urban Heat ◽

Thermal Buffering

AbstractAnthropogenically-driven climate warming is a hypothesized driver of animal body size reductions. Less understood are effects of other human-caused disturbances on body size, such as urbanization. We compiled 140,499 body size records of over 100 North American mammals to test how climate and human population density, a proxy for urbanization, and their interactions with species traits, impact body size. We tested three hypotheses of body size variation across urbanization gradients: urban heat island effects, habitat fragmentation, and resource availability. Our results demonstrate that both urbanization and temperature influence mammalian body size variation, most often leading to larger individuals, thus supporting the resource availability hypothesis. In addition, life history and other ecological factors play a critical role in mediating the effects of climate and urbanization on body size. Larger mammals and species that utilize thermal buffering are more sensitive to warmer temperatures, while flexibility in activity time appears to be advantageous in urbanized areas. This work highlights the value of using digitized, natural history data to track how human disturbance drives morphological variation.

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Diversity of Algae and Cyanobacteria and Bioindication Characteristics of the Alpine Lake Nesamovyte (Eastern Carpathians, Ukraine) from 100 Years Ago to the Present

Diversity ◽

10.3390/d13060256 ◽

2021 ◽

Vol 13 (6) ◽

pp. 256

Author(s):

Petro M. Tsarenko ◽

Olena P. Bilous ◽

Olha M. Kryvosheia-Zakharova ◽

Halyna H. Lilitska ◽

Sophia Barinova

Keyword(s):

Species Composition ◽

Structural Changes ◽

Algal Species ◽

Taxonomic Composition ◽

Alpine Lake ◽

Algal Flora ◽

Ecological Analysis ◽

Modern Species ◽

Eastern Carpathians ◽

Infraspecific Taxa

The species diversity and changes in the structural dynamics of the algal flora from the alpine lake Nesamovyte has been studied for 100 years. During the period of investigations, 234 species (245 infraspecific taxa) were revealed to cover more than 70% of the modern species composition of the studied lake. The modern biodiversity of algae is characterized by an increase in the number of widespread forms, a change from the baseline “montane” complex in comparison to the beginning of the 20th century. Nevertheless, the Nesamovyte Lake still has a unique algae composition that is typical for high-mountainous European lakes. The presence of a different complex of conventionally arctic species of algae, in particular, diatoms is discussed. Structural changes in the taxonomic composition of the algal flora of the lake as well as in the complex of the leading genera, species and their diversity are revealed. An ecological analysis of the algal species composition of the lake showed vulnerability and degradation to the ecosystem of the lake. On this basis, the issue regarding the question of protection and preservation of the algae significance and uniqueness of the flora of algae in the Nesamovyte Lake are discussed.

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