scholarly journals The Effects of Roughness and Wetness on Salamander Cling Performance

2020 ◽  
Vol 60 (4) ◽  
pp. 840-851
Author(s):  
Mary Kate O’Donnell ◽  
Stephen M Deban
Keyword(s):  
Surface Properties ◽  
Geographical Range ◽  
Large Species ◽  
Small Species ◽  
Plant Leaves ◽  
Substrate Roughness ◽  
Plethodontid Salamanders ◽  
Dry And Wet Conditions ◽  
Flowing Stream ◽  
Soil And Water

Synopsis Animals clinging to natural surfaces have to generate attachment across a range of surface roughnesses in both dry and wet conditions. Plethodontid salamanders can be aquatic, semi-aquatic, terrestrial, arboreal, troglodytic, saxicolous, and fossorial and therefore may need to climb on and over rocks, tree trunks, plant leaves, and stems, as well as move through soil and water. Sixteen species of salamanders were tested to determine the effects of substrate roughness and wetness on maximum cling angle. Substrate roughness had a significant effect on maximum cling angle, an effect that varied among species. Substrates of intermediate roughness (asperity size 100–350 µm) resulted in the poorest attachment performance for all species. Small species performed best on smooth substrates, while large species showed significant improvement on the roughest substrates (asperity size 1000–4000 µm), possibly switching from mucus adhesion on a smooth substrate to an interlocking attachment on rough substrates. Water, in the form of a misted substrate coating and a flowing stream, decreased cling performance in salamanders on smooth substrates. However, small salamanders significantly increased maximum cling angle on wetted substrates of intermediate roughness, compared with the dry condition. Study of cling performance and its relationship to surface properties may cast light onto how this group of salamanders has radiated into the most speciose family of salamanders that occupies diverse habitats across an enormous geographical range.

scholarly journals Comparative growth, age at maturity and sex change, and longevity of Hawaiian parrotfishes, with bomb radiocarbon validation

2018 ◽  
Vol 75 (4) ◽  
pp. 580-589 ◽  
Author(s):  
Edward E. DeMartini ◽  
Allen H. Andrews ◽  
Kathrine G. Howard ◽  
Brett M. Taylor ◽  
Dong-Chun Lou ◽  
...  
Keyword(s):  
Fork Length ◽  
Logistic Models ◽  
Growth Curves ◽  
Sex Change ◽  
Terminal Phase ◽  
Large Species ◽  
Small Species ◽  
Bomb Radiocarbon ◽  
Current Minimum ◽  
Fishery Species

Growth rates and longevities were estimated for five major fishery species of parrotfishes (“uhu”) at Oahu, Hawai’i. All species grew rapidly with von Bertalanffy growth formula k values ≥0.4·year−1. Longevities were found to range broadly among the three small species, 4 years in Calotomus carolinus and 6 and 11 years in Scarus psittacus and Chlorurus spilurus, and to 15–20 years in Scarus rubroviolaceus and Chlorurus perspicillatus for the two large species. Age reading and growth curves for the latter two large species were validated using bomb radiocarbon dating. Median ages at sexual maturity as females (AM50) and at sex change (from female to terminal phase male, AΔ50) were estimated using logistic models. Sexual maturation occurred at 1–2 years for the small species and at 3–3.5 years in the large species. AΔ50 estimates ranged from 2 to 4 years in the small species and were about 5 and 7 years in S. rubroviolaceus and C. perspicillatus, respectively. Estimated milestones poorly corresponded to the current minimum legal size for uhu in Hawai’i (12 in. or 30.5 cm fork length). Pooling these parrotfishes for management seems generally inappropriate, especially for the two large species. Age-based metrics are more informative than size-based metrics for these fishes.

The first specimen of Deinotherium indicum (Mammalia, Proboscidea, Deinotheriidae) from the late Miocene of Kutch, India

2020 ◽  
Vol 94 (4) ◽  
pp. 788-795 ◽  
Author(s):  
Ningthoujam Premjit Singh ◽  
Advait M. Jukar ◽  
Rajeev Patnaik ◽  
K. Milankumar Sharma ◽  
Nongmaithem Amardas Singh ◽  
...  
Keyword(s):  
South Asian ◽  
Late Miocene ◽  
Indian Subcontinent ◽  
Morphological Diversity ◽  
Western India ◽  
Large Species ◽  
Small Species ◽  
Old World ◽  
First Occurrence

AbstractDeinotheriidae Bonaparte, 1845 is a family of browsing proboscideans that were widespread in the Old World during the Neogene. From Miocene deposits in the Indian subcontinent, deinotheres are known largely from dental remains. Both large and small species have been described from the region. Previously, only small deinothere species have been identified from Kutch in western India. In the fossiliferous Tapar beds in Kutch, dental remains have been referred to the small species Deinotherium sindiense Lydekker, 1880, but the specimens are too fragmentary to be systematically diagnostic. Here, we describe a large p4 of a deinothere from the Tapar beds and demonstrate that it is morphologically most similar to Deinotherium indicum Falconer, 1845, a large species of deinothere, thereby confirming the identity of deinotheres at Tapar. Deinotherium indicum from Tapar is larger than other deinotheres identified from Kutch and is the first occurrence of the species in the region. This new specimen helps constrain the age of the Tapar beds to the Tortonian and increases the biogeographic range of this species—hitherto only known from two localities on the subcontinent. This specimen also highlights the morphological diversity of South Asian deinothere p4s and allows us to reassess dental apomorphies used to delimit Indian deinothere species. Lastly, we argue that by the late Miocene, small deinotheres in Kutch were replaced by the large Deinotherium indicum.

Velloziaceae in honorem appellatae

Phytotaxa ◽  
2014 ◽  
Vol 175 (2) ◽  
pp. 85 ◽  
Author(s):  
Renato Mello-Silva ◽  
NANUZA LUIZA DE MENEZES
Keyword(s):  
New Species ◽  
Minas Gerais ◽  
Large Species ◽  
Small Species ◽  
Fourth Species

Four new species of Vellozia are described and named after people linked to Velloziaceae and Brazilian botany. Vellozia everaldoi, V. giuliettiae, V. semirii and V. strangii are endemic to the Diamantina Plateau in Minas Gerais, Brazil. Vellozia giuliettiae and V. semirii are small species that share characteristics that would assign them to Vellozia sect. Xerophytoides, which include an ericoid habit with no leaf furrows and six stamens. Vellozia everaldoi, although a small, ericoid species, could not be placed in that section because it has conspicuous furrows, although it is considered closely related to species of that section. The fourth species, V. strangii, is a relative large species closely related to V. hatschbachii. Descriptions and illustrations of the species are followed by a discussion of their characteristics and putative relationships.

The flight of petrels and albatrosses (procellariiformes), observed in South Georgia and its vicinity

1982 ◽  
Vol 300 (1098) ◽  
pp. 75-106 ◽  
Keyword(s):  
Body Mass ◽  
The Body ◽  
Large Species ◽  
Small Species ◽  
Classical Dynamic ◽  
South Georgia ◽  
Mass Comparison ◽  
Gliding Flight ◽  
Field Season ◽  
Simple Power Function

Nine procellariiform species, covering a range of body mass exceeding 200: 1, were studied during a visit to Bird Island, South Georgia, with the British Antarctic Survey, in the 1979-1980 field season. Speed measurements were made by ornithodolite of birds slope-soaring over land, birds flying over the sea but observed from land, and birds observed from a ship. In the second group, which showed the least anomalies, lift coefficients corresponding to mean airspeeds were about 1 for albatrosses, decreasing to about 0.3 for the smallest petrels. All species increased speed when flying against the wind. The small species proceeded by flap-gliding, while the large ones flapped infrequently, and only in light winds. The small species flew lower than the larger ones, but this may be related to the fact that most of the observations were of birds flying into wind. The albatrosses ( Diomedea, Phoebetria ) and giant petrels ( Macronectes ) were found to have a ‘shoulder lock’, consisting of a tendon sheet associated with the pectoralis muscle, which restrained the wing from elevation above the horizontal. This arrangement was not seen in the smaller species, and was interpreted as an adaptation reducing the energy cost of gliding flight. The main soaring method in the large species appeared to be slope-soaring along waves. Windward ‘pullups’ suggestive of the classical ‘dynamic soaring’ technique were seen in large and medium-sized species. However, the calculated strength of the wind gradient would have been insufficient to maintain airspeed to the heights observed, and it was concluded that most of the energy for the pullups must come from kinetic energy, acquired by gliding along a wave in slope lift. Gliding downwind through the wind gradient should significantly increase the glide ratio, but this was not observed. Slope-soaring along moving waves in zero wind was recorded. The data were used to derive estimates of the average speeds that the different species should be able to maintain on foraging expeditions. Estimates of the rate of energy consumption were also made, taking into account the greater dependence on flapping in the smaller species, and on soaring in the larger ones. The distance travelled in consuming fuel equivalent to a given fraction of the body mass would seem to be very strongly dependent on mass. Comparison of the largest species ( Diomedea exulans ) with the smallest ( Oceanites oceanicus ) suggests that ‘range’, defined in this way, varies as the 0.60 power of the mass, although the relation is more complex than a simple power function.

Instar Increments in Copepod Growth

1986 ◽  
Vol 43 (8) ◽  
pp. 1671-1674 ◽  
Author(s):  
Alan R. Longhurst
Keyword(s):  
Growth Patterns ◽  
Large Species ◽  
Adult Size ◽  
Small Species

There is a difference in the growth patterns of large and small copepods as indicated by lengths at each instar for 55 species of copepods from all latitudes. Large species put on a greater proportion of their adult size relatively late in life compared with small species. This confirms an earlier suggestion based on a comparison of only two species.

Systemic range shift lags among a pollinator species assemblage following rapid climate change1This article is part of a Special Issue entitled “Pollination biology research in Canada: Perspectives on a mutualism at different scales”.

Botany ◽  
2012 ◽  
Vol 90 (7) ◽  
pp. 587-597 ◽  
Author(s):  
Felicity E. Bedford ◽  
Robert J. Whittaker ◽  
Jeremy T. Kerr
Keyword(s):  
Climate Change ◽  
Climatic Conditions ◽  
Range Shift ◽  
Range Shifts ◽  
Geographical Range ◽  
Large Species ◽  
Species Assemblage ◽  
Mobile Species ◽  
Recent Climate ◽  
Winter Temperatures

Contemporary climate change is driving widespread geographical range shifts among many species. If species are tracking changing climate successfully, then leading populations should experience similar climatic conditions through time as new populations establish beyond historical range margins. Here, we investigate geographical range shifts relative to changing climatic conditions among a particularly well-sampled assemblage of butterflies in Canada. We assembled observations of 81 species and measured their latitudinal displacement between two periods: 1960–1975 (a period of little climate change) and 1990–2005 (a period with large climate change). We find an unexpected trend for species’ northern borders to shift progressively less relative to increasing minimum winter temperatures in northern Canada. This study demonstrates a novel, systemic latitudinal gradient in lags among a large species assemblage in responses to recent climate change. Even among the most mobile species and without anthropogenic barriers to dispersal, these pollinators have been unable to extend their ranges as fast as required to keep pace with climate change.

scholarly journals The scaling of expansive energy under the Red Queen predicts Cope’s Rule

2019 ◽  
Author(s):  
Indrė Žliobaitė ◽  
Mikael Fortelius
Keyword(s):  
Body Size ◽  
Population Growth ◽  
Body Mass ◽  
Limiting Factor ◽  
Large Species ◽  
Small Species ◽  
Evolutionary Advantage ◽  
Zero Sum ◽  
The Red Queen ◽  
Cope’S Rule

AbstractThe Red Queen’s hypothesis portrays evolution as a never-ending competition for expansive energy, where one species’ gain is another species’ loss. The Red Queen is neutral with respect to body size, implying that neither small nor large species have a universal competitive advantage. The maximum population growth in ecology; however, clearly depends on body size – the smaller the species, the shorter the generation length, and the faster it can expand. Here we ask whether, and if so how, the Red Queen’s hypothesis can accommodate a spectrum of body sizes. We theoretically analyse scaling of expansive energy with body mass and demonstrate that in the Red Queen’s zero-sum game for resources, neither small nor large species have a universal evolutionary advantage. We argue that smaller species have an evolutionary advantage only when resources in the environment are not fully occupied, such as after mass extinctions or following key innovations allowing expansion into freed up or previously unoccupied resource space. Under such circumstances, we claim, generation length is the main limiting factor for population growth. When competition for resources is weak, smaller species can indeed expand faster, but to sustain this growth they also need more resources. In the Red Queen’s realm, where resources are fully occupied and the only way for expansion is to outcompete other species, acquisition of expansive energy becomes the limiting factor and small species lose their physiological advantage. A gradual transition from unlimited resources to a zero-sum game offers a direct mechanistic explanation for observed body mass trends in the fossil record, known as Cope’s Rule. When the system is far from the limit of resources and competition is not maximally intense, small species take up ecological space faster. When the system approaches the limits of its carrying capacity and competition tightens, small species lose their evolutionary advantage and we observe a wider range of successful body masses, and, as a result, an increase in the average body mass within lineages.

scholarly journals The type of forest edge governs the spatial distribution of different-sized ground beetles

2020 ◽  
Vol 66 (Suppl.) ◽  
pp. 69-96
Author(s):  
Tibor Magura ◽  
Gábor L. Lövei
Keyword(s):  
Body Size ◽  
Human Disturbance ◽  
Forest Edge ◽  
Ground Beetles ◽  
The Body ◽  
Large Species ◽  
Forest Edges ◽  
Small Species ◽  
Natural Processes ◽  
Species Tolerance

Worldwide human-induced habitat fragmentation intensifies the emergence of forest edges. In addition to these edges, there are edges evolved by natural processes. Edge-maintaining processes (natural vs. anthropogenic) fundamentally determine edge responses, and thus edge functions. Species with various traits show fundamentally different edge response, therefore the trait-based approach is essential in edge studies. We evaluated the edge effect on the body size of ground beetles in forest edges with various maintaining processes. Our results, based on 30 published papers and 221 species, showed that natural forest edges were impenetrable for small species, preventing their dispersal into the forest interiors, while both the medium and the large species penetrated across these edges and dispersed into the forest interiors. Anthropogenic edges maintained by continued human disturbance (agriculture, forestry, urbanisation) were permeable for ground beetles of all size, allowing them to invade the forest interiors. Overwintering type (overwintering as adults or as larvae) was associated with body size, since almost two-thirds of the small species, while slightly more than a third of both the medium and the large species were adult overwintering. Based on this, size-dependent permeability of natural edges may be related to overwintering type, which basically determines species tolerance to human disturbance.

Speciation, Extinction, and the Distribution of Phylogenetic Diversity

2016 ◽  
Author(s):  
Marc W. Cadotte ◽  
T. Jonathan Davies
Keyword(s):  
Species Richness ◽  
Spatial Variation ◽  
Evolutionary History ◽  
Phylogenetic Diversity ◽  
Life Forms ◽  
Conservation Strategy ◽  
Large Species ◽  
Small Species ◽  
Phylogenetic Methods ◽  
Diversity Of Life

This chapter examines the use of phylogenetic methods to explain macroevolutionary trends in speciation, extinction, and the distribution of phylogenetic diversity across space and through time. The diversity of life is unevenly distributed across the globe. Species richness tends to be higher at lower latitudes and elevations, and the distribution of life forms also varies across space. For example, Foster's rule suggests that on islands small species evolve to become bigger, while large species evolve to become smaller. Equally, the distribution of evolutionary history shows large spatial variation, reflecting the histories of speciation, extinction, and dispersal. This chapter first considers how large, global phylogenies make it possible to map the distribution of phylogenetic diversity and develop a conservation strategy to maximize coverage of the tree of life. It then discusses the variation in diversification across spatiotemporal gradients and shows that phylogenetic diversity covaries significantly with taxonomic richness.

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