scholarly journals Inter-Individual Differences in Ornamental Colouration in a Mediterranean Lizard in Relation to Altitude, Season, Sex, Age, and Body Traits

Diversity ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 158
Author(s):  
Gregorio Moreno-Rueda ◽  
Senda Reguera ◽  
Francisco J. Zamora-Camacho ◽  
Mar Comas
Keyword(s):  
Elevational Gradient ◽  
Head Size ◽  
Long Distance ◽  
Altitudinal Variation ◽  
Light Yellow ◽  
Psammodromus Algirus ◽  
Colour Saturation ◽  
Colour Patterns ◽  
Different Sources ◽  
Colour Signals

Animals frequently show complex colour patterns involved in social communication, which attracts great interest in evolutionary and behavioural ecology. Most researchers interpret that each colour in animals with multiple patches may either signal a different bearer’s trait or redundantly convey the same information. Colour signals, moreover, may vary geographically and according to bearer qualities. In this study, we analyse different sources of colour variation in the eastern clade of the lizard Psammodromus algirus. Sexual dichromatism markedly differs between clades; both possess lateral blue eyespots, but whereas males in the western populations display strikingly colourful orange-red throats during the breeding season, eastern lizards only show some commissure pigmentation and light yellow throats. We analyse how different colour traits (commissure and throat colouration, and the number of blue eyespots) vary according to body size, head size (an indicator of fighting ability), and sex along an elevational gradient. Our findings show that blue eyespots function independently from colour patches in the commissure and throat, which were interrelated. Males had more eyespots and orange commissures (which were yellow or colourless in females). Throat colour saturation and the presence of coloured commissures increased in older lizards. The number of eyespots, presence of a coloured commissure, and throat colour saturation positively related to head size. However, while the number of eyespots was maximal at lowlands, throat colour saturation increased with altitude. Overall, our results suggest that this lizard harbours several colour signals, which altitudinally differ in their importance, but generally provide redundant information. The relevance of each signal may depend on the context. For example, all signals indicate head size, but commissure colouration may work well at a short distance and when the lizard opens the mouth, while both throat and eyespots might work better at long distance. Meanwhile, throat colouration and eyespots probably work better in different light conditions, which might explain the altitudinal variation in the relative importance of each colour component.

Trade, Commerce, and the State in the Roman World

2017 ◽  
Keyword(s):  
Roman Empire ◽  
The State ◽  
Market Regulation ◽  
External Trade ◽  
Long Distance ◽  
Legal Structures ◽  
The City ◽  
Political Character ◽  
Different Sources

This interdisciplinary volume presents nineteen chapters by Roman historians and archaeologists, discussing trade in the Roman Empire in the period c.100 BC to AD 350, and in particular the role of the Roman state, in shaping the institutional framework for trade within and outside the Empire, in taxing that trade, and in intervening in the markets to ensure the supply of particular commodities, especially for the city of Rome and for the army. The chapters in this volume address facets of the subject on the basis of widely different sources of evidence—historical, papyrological, and archaeological—and are grouped in three sections: institutional factors (taxation, legal structures, market regulation, financial institutions); evidence for long-distance trade within the Empire, in wood, stone, glass, and pottery; and trade beyond the frontiers, with the East (as far as China), India, Arabia, and the Red Sea, and the Sahara. Rome’s external trade with realms to the east emerges as being of particular significance to the fisc. But in the eastern part of the Empire at least, the state appears, in collaboration with the elite holders of wealth, to have adapted the mechanisms of taxation, both direct and indirect, to support its need for revenue. On the other hand, the price of that collaboration, which was in effect a fiscal partnership, in slightly different forms in East and West, in the longer term fundamentally changed the political character of the Empire.

scholarly journals Age structure of a lizard along an elevational gradient reveals nonlinear lifespan patterns with altitude

2019 ◽  
Vol 66 (4) ◽  
pp. 373-382 ◽  
Author(s):  
Mar Comas ◽  
Senda Reguera ◽  
Francisco J Zamora-Camacho ◽  
Gregorio Moreno-Rueda
Keyword(s):  
Life History ◽  
Sierra Nevada ◽  
Food Availability ◽  
Reproductive Investment ◽  
Elevational Gradient ◽  
Activity Time ◽  
Psammodromus Algirus ◽  
Limited Food ◽  
Main Components ◽  
Marginal Habitats

Abstract Lifespan is one of the main components of life history. Shorter lifespans can be expected in marginal habitats. However, in the case of ectotherms, lifespan typically increases with altitude, even though temperature—one of the main factors to determine ectotherms’ life history—declines with elevation. This pattern can be explained by the fact that a shorter activity time favors survival. In this study, we analyzed how lifespan and other life-history traits of the lizard Psammodromus algirus vary along a 2,200 m elevational gradient in Sierra Nevada (SE Spain). Populations at intermediate altitudes (1,200–1,700 m), corresponding to the optimal habitat for this species, had the shortest lifespans, whereas populations inhabiting marginal habitats (at both low and at high altitudes) lived longest. Therefore, this lizard did not follow the typical pattern of ectotherms, as it also lived longer at the lower limit of its distribution, nor did it show a longer lifespan in areas with optimal habitats. These results might be explained by a complex combination of different gradients along the mountain, namely that activity time decreases with altitude whereas food availability increases. This could explain why lifespan was maximum at both high (limited activity time) and low (limited food availability) altitudes, resulting in similar lifespans in areas with contrasting environmental conditions. Our findings also indicated that reproductive investment and body condition increase with elevation, suggesting that alpine populations are locally adapted.

scholarly journals Prey availability, prey selection, and trophic niche width in the lizard Psammodromus algirus along an elevational gradient

2017 ◽  
Vol 64 (5) ◽  
pp. 603-613 ◽  
Author(s):  
Gregorio Moreno-Rueda ◽  
Elena Melero ◽  
Senda Reguera ◽  
Francisco J Zamora-Camacho ◽  
Inés Álvarez-Benito
Keyword(s):  
Prey Availability ◽  
Prey Selection ◽  
Elevational Gradient ◽  
Trophic Niche ◽  
Niche Width ◽  
Psammodromus Algirus

scholarly journals Low genome-wide divergence between two lizard populations with high adaptive phenotypic differentiation

2021 ◽  
Author(s):  
Alejandro Llanos-Garrido ◽  
Javier Pérez-Tris ◽  
José Díaz
Keyword(s):  
Local Adaptation ◽  
Genetic Divergence ◽  
Elevational Gradient ◽  
Phenotypic Differentiation ◽  
Genome Wide ◽  
Isolation By Environment ◽  
Psammodromus Algirus ◽  
Low Levels ◽  
Two Populations ◽  
Degree Of Isolation

Usually, adaptive phenotypic differentiation is paralleled by genetic divergence between locally adapted populations. However, adaptation can also happen in a scenario of non-significant genetic divergence due to intense gene flow and/or recent differentiation. While this phenomenon is rarely published, findings on incipient ecologically-driven divergence or isolation by adaptation are relatively common, which could confound our understanding about the frequency at which they actually occur in nature. Here, we explore genome-wide traces of divergence between two populations of the lacertid lizard Psammodromus algirus separated by a 600 m elevational gradient. These populations seem to be differentially adapted to their environments despite showing low levels of genetic differentiation (according to previously studies of mtDNA and microsatellite data). We performed a search for outliers (i.e. loci subject to selection) trying to identify specific loci with FST statistics significantly higher than those expected on the basis of overall, genome-wide estimates of genetic divergence. We find that local phenotypic adaptation (in terms of a wide diversity of characters) was not accompanied by genome-wide differentiation, even when we maximized the chances of unveiling such differentiation at particular loci with FST-based outlier detection tests. Instead, our analyses confirmed the lack of differentiation on the basis of more than 70,000 SNPs, which is concordant with a scenario of local adaptation without any degree of isolation by environment. Our results add evidence to previous studies in which local adaptation does not lead to any kind of isolation (or early stages of ecological speciation), but maintains phenotypic divergence despite the lack of a differentiated genomic background.

scholarly journals BERENIKE CROSSROADS: THE INTEGRATION OF INFORMATION

2003 ◽  
Vol 46 (1) ◽  
pp. 46-87 ◽  
Author(s):  
◽  
◽  
◽  
◽  
◽  
...  
Keyword(s):  
Indian Ocean ◽  
Preliminary Analysis ◽  
Historical Context ◽  
Ocean Basin ◽  
Third Century ◽  
Long Distance ◽  
Textual Evidence ◽  
The Third ◽  
The Indian Ocean ◽  
Different Sources

AbstractThe harbor town of Berenike functioned in the long-distance trade between the Mediterranean and the Indian Ocean Basin from the third century BC to the early sixth century AD. This contribution aims to view the Berenike material within its wider historical context through a preliminary analysis of the combined archaeological and textual evidence. By comparing the results of the work of different specialists, the potential of a multi-disciplinary approach becomes apparent. A number of caveats are given, which illustrate the interpretative problems arising from comparing the results of different disciplines. Lastly, this attempt at integration shows that the discrepancies between the different sources offer important insights. Le port maritime de Berenike fonctionnait dans le commerce de longue distance entre la Méditerranée et le bassin de la Mer des Indes depuis le troisième siècle avant JC jusqu'au début du sixième siècle après JC. Cette contribution examine le matériel de Berenike dans un contexte plus large par une analyse préliminaire croisant des données archéologiques et textuelles. En comparant les résultats proposés par plusieurs spécialistes, le potentiel du travail multidisciplinaire devient évident. Un nombre de caveats est présenté pour illustrer des problèmes d'interprétation, provenant des comparaisons de résultats de plusieurs disciplines. Enfin, cet essai d'intégration montre que les divergences entre plusieurs sources offre des aperçus importants.

scholarly journals Variation in colour signals among Sarracenia pitcher plants and the potential role of areoles in the attraction of flying Hymenoptera

2021 ◽  
Author(s):  
Corentin Dupont ◽  
Claire Villemant ◽  
Tom Hattermann ◽  
Jeremie Pratviel ◽  
Laurence Gaume ◽  
...  
Keyword(s):  
Potential Role ◽  
Prey Capture ◽  
Visual Signal ◽  
Visual Features ◽  
Prey Composition ◽  
Insectivorous Plants ◽  
Visual Characteristics ◽  
Colour Patterns ◽  
Colour Signals

Sarracenia insectivorous plants show a diversity of visual features in their pitchers but their perception by insects and their role in attraction, have received little attention. They also vary in prey composition, with some species trapping more flying Hymenoptera, such as bees. To test the hypothesis of a link between visual signal variability and prey segregation ability, and to identify which signal could attract flying Hymenoptera, we characterised, the colour patterns of 32 pitchers belonging to four taxa, modelled their perception by flying Hymenoptera, and examined the prey they trapped. The pitchers of the four taxa differed in colour patterns, with notably two long-leaved taxa displaying clear areoles, which contrasted strongly in colour and brightness with the vegetative background and with other pitcher areas in the eyes of flying Hymenoptera. These taxa trapped high proportion of flying hymenoptera. This suggests that contrasting areoles may act as a visual lure for flying Hymenoptera, making plants particularly visible to these insects. Prey capture also differed according to pitcher stage, morphology, season and visual characteristics. Further studies on prey visitation are needed to better understand the link between prey capture and attraction feature.

Thermoregulation in the lizard Psammodromus algirus along a 2200-m elevational gradient in Sierra Nevada (Spain)

2015 ◽  
Vol 60 (5) ◽  
pp. 687-697 ◽  
Author(s):  
Francisco Javier Zamora-Camacho ◽  
Senda Reguera ◽  
Gregorio Moreno-Rueda
Keyword(s):  
Sierra Nevada ◽  
Elevational Gradient ◽  
Psammodromus Algirus
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