Body Size and Growth in Two Populations of the Puerto Rican Ground Lizard (Teiidae)

1986 ◽  
Vol 20 (2) ◽  
pp. 190 ◽  
Author(s):  
Allen R. Lewis
Genetics ◽  
2003 ◽  
Vol 165 (2) ◽  
pp. 667-673 ◽  
Author(s):  
W Jason Kennington ◽  
Julia Gockel ◽  
Linda Partridge

AbstractAsymmetrical gene flow is an important, but rarely examined genetic parameter. Here, we develop a new method for detecting departures from symmetrical migration between two populations using microsatellite data that are based on the difference in the proportion of private alleles. Application of this approach to data collected from wild-caught Drosophila melanogaster along a latitudinal body-size cline in eastern Australia revealed that asymmetrical gene flow could be detected, but was uncommon, nonlocalized, and occurred in both directions. We also show that, in contrast to the findings of a previous study, there is good evidence to suggest that the cline experiences significant levels of gene flow between populations.


2011 ◽  
Vol 71 (1) ◽  
pp. 189-196 ◽  
Author(s):  
LR. Forti ◽  
ASO. Tissiani ◽  
T. Mott ◽  
C Strüssmann

The understanding of feeding habits is important for anurans in general, both from an ecological and a phylogenetic perspective. For diurnal poison frogs belonging to the Dendrobatidae family, diet aspects play a crucial role in their defense and survival. Herein, we investigated feeding habits, foraging behaviour, and overall effects of habitat, sex, and body size on the diet of individuals of Ameerega braccata, a poorly known dendrobatid species. Specimens were observed and collected in the type-locality, Chapada dos Guimarães, and in the neighbouring municipality of Cuiabá, both in the State of Mato Grosso, Midwestern Brazil. The most important prey categories for A. braccata were Formicidae, Isoptera, and Acari, whose representatives were caught during active foraging. Individuals from Chapada dos Guimarães population consumed more Acari but fewer Isoptera than individuals from Cuiabá. Despite this, niche breadth values were narrow and similar for the two populations. Individuals from two distinct habitats (campo sujo and cerrado stricto sensu) showed differences in their diet, probably as an effect of differential prey availability. Females consumed more Isoptera than males. The number of prey categories used as food was not influenced by the variation of body size of the target species. However, the abundance and the volume of consumed Acari were statistically correlated with body size. The main results suggest that Ameerega braccata has a narrow niche breadth, as well as a specialised diet in ants, termites, and mites, which reinforces the hypotheses of close association between Acari consumption and the presence of skin toxic alkaloids, already found in other species of Dendrobatidae. Although differences in prey consumption between sexes are uncommon among poisonous frogs, differences in the diet composition between age classes, which probably reduce intraspecific competition, are frequently reported.


2020 ◽  
Vol 131 (3) ◽  
pp. 656-666
Author(s):  
Abraham Lozano ◽  
Aurelio Ramírez-Bautista ◽  
Raciel Cruz-Elizalde

Abstract Morphological adaptations of individuals are directly (or indirectly) determined by the environment. Depending on sex, these adaptations may vary in different ways, given that different selective forces may be operating on organisms. Here, we evaluate intraspecific morphological variation (size and shape) in two populations of Sceloporus grammicus that occur in different structural habitats (trees and rocks). No difference in overall body size was found between the two populations. However, strong differences were found in body shape; the tree population was characterized by having shorter hindlimb proportions than the rock population, which agrees with the theory of biomechanical models. Furthermore, our results show that this species is dimorphic in size and shape, both in sex and population effects. A review of the literature suggests that the large overall body size and relatively longer distal segments of males could be an advantage for defending their territory, and the observation that females had relatively longer head length may be related to trophic niche divergence; however, this remains to be tested. Detailed quantification of behaviour, performance and reproductive characteristics must be performed to shed light on the evolution of sexual dimorphism in this widely distributed species in Mexico.


Author(s):  
Jan Kuper

The life-history and behaviour of the chironomid Metriocnemus (Inermipupa) carmencitabertarum was studied for three years and a comparison was made between two populations in the Netherlands. Key life-history characteristics are reported, including the number of generations (2-5 generations) and duration of larval development (19-55 days). Life-history characteristics differed between the two populations and between generations within a population. These differences were likely related to differences in competitors (mainly Chironomus riparius Meigen) and thermal characteristics of the habitat from variations in water volume and ambient temperature. Results suggested a diapause in summer, when water levels dropped, and not in winter. A clear seasonal pattern in body size was found with pupal length increasing steeply at the beginning of the summer. The increase in body size was positively correlated with mean ambient temperature during larval development. This correlation is in contrast with the Temperature-Size Rule (TSR) in ectotherms, which postulates a negative correlation between temperature and adult body size. The chance of ectotherm predators being present in the habitat is low, which may explain this feature. Life history characteristics supported a recent northward range expansionfor M. (I.) carmencitabertarum due to warmer winters. If correct, it is predicted that the species will be found in Scotland and northern Germany and/or southern Denmark in the near future.


2019 ◽  
Vol 21 (2) ◽  
Author(s):  
Germund Tyler

Objectives are to elucidate whether populations of Carabus arvensis Herbst, 1784 from contrasting habitats differ in (i) colour, (ii) brightness of metal lustre, or (iii) body size (length of elytra, of elytra + pronotum, and width of pronotum). Two large populations were studied, originating from (a) open heathland, being a remnant from more widespread heaths during former centuries, and (b) mature pine forest established 100–150 years ago on sandy agricultural land. Heath individuals had significantly more brilliant metal lustre and mostly lighter, vivid copper colour than pine forest individuals, which were typically black with a violet shade and slightly larger in size. The two populations are nowadays isolated, which was probably not the case 1–2 centuries ago, when both sites studied were treeless. The usually blackish colour of the forest population could be a recent adaptation to the changed environment, though some influence of processes such as genetic drift cannot be excluded.


2012 ◽  
Vol 81 (4) ◽  
pp. 311-320 ◽  
Author(s):  
Jakub Michalcewicz ◽  
Michał Ciach

ABSTRACT.The body size of xylophagous beetles is determined by the host plant species, as well as by the amount and quality of breeding material. Consequently, the biometric traits of adults can be used as an indicator of the attractiveness of the breeding material and the quality of a habitat. The paper presents selected biometric traits of rosalia longicornRosalia alpina(L.) imagines in three populations from the Beskid Niski Mts (Carpathian Mts, south-eastern Poland). Two populations of this beetle from managed forests and one from a protected area in the Magura National Park were compared. The former developed on two different host plants (European beechFagus sylvaticaand wych elmUlmus glabra), the latter on European beech. No significant differences were found between the biometric traits of imagines from the three populations. No intersexual differences were found for the width of the pronotum in any of the populations, but females had longer elytra than males in all the populations. The lack of body size differences in these populations potentially indicates that this species occurs only in favourable habitat conditions. The limited species range and the patchy distribution of the rosalia longicorn are indications of its stringent habitat requirements and its dependence on forest management. Habitats supplying a sufficient amount and quality of suitable breeding material for the development of the rosalia longicorn should be protected.


2011 ◽  
Vol 78 (2) ◽  
pp. 215-221 ◽  
Author(s):  
Wen Bo Liao ◽  
Xin Lu ◽  
Yue Wu Shen ◽  
Jin Chu Hu

1980 ◽  
Vol 58 (11) ◽  
pp. 1992-1996 ◽  
Author(s):  
Kim W. Strong ◽  
Graham R. Daborn

Effects of temperature on ingestion (C) and metabolic (R) rates in Idotea baltica are examined to explain differences in maximum body size, longevity, and seasonal occurrence in two populations occupying habitats differing by 2–4 °C in average maximum temperature. Results illustrate that C and R are differentially affected by temperature such that the value C – R varies considerably with both body size and temperature. These data indicate that small isopods (< 20 mg) would grow most rapidly at the highest temperature studied (14 °C), whereas larger animals have maximum C – R values, and presumably grow most rapidly, at cooler temperatures (ca. 9 °C). The pattern explains why the population at the lower temperature lives twice as long, grows to much larger size, and apparently leaves the intertidal zone for a longer period than do those living in the similar warmer habitat. The results are discussed in relation to phenomena noted in other marine and freshwater crustacean populations.


Author(s):  
Erik V. Thuesen ◽  
Kelly D. McCullough ◽  
James J. Childress

This study compared the scaling of the glycolytic enzyme lactate dehydrogenase (LDH) and the Krebs cycle enzyme citrate synthase (CS) in the swimming muscle and tentacle tissue of the mesopelagic coronate scyphomedusa Periphylla periphylla in two populations living under different oxygen minimum layer conditions. The LDH and CS activities in these tissues of two other coronate scyphomedusae (Paraphyllina ransoni and Periphyllopsis galatheae) and the bathypelagic narcomedusa Aegina citrea were also studied. The scaling of these two enzymes along with total protein was investigated in whole organism homogenates of the surface-living scyphomedusa Aurelia labiata. Mass-specific LDH activities in swimming muscle showed positive scaling in relation to body size in Periphylla periphylla collected off California and Hawaii. Mass-specific LDH activities in tentacle tissue increased with regards to increasing mass only in specimens of P. periphylla collected off California. The LDH values of the scaling coefficient, b, in swimming muscle and tentacle were significantly higher in P. periphylla collected in the low oxygen waters off California than from those collected off the Hawaiian Islands in a higher oxygen environment. The LDH showed a significant decrease with body size in Aegina citrea swimming muscle and in Aurelia labiata whole animal homogenates. The largest species in this study, Periphyllopsis galatheae, had LDH activities similar to the smallest specimens of Periphylla periphylla. The results of this study suggest that the scaling of glycolytic activity is related to oxygen availability for P. periphylla. In Aurelia labiata, which is only exposed to episodic hypoxia, and Aegina citrea, scaling of glycolytic activity is not affected by oxygen availability.


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