PATTERNS IN MAYFLY (EPHEMEROPTERA) WING LENGTH: ADAPTATION TO DISPERSAL?

1987 ◽  
Vol 119 (9) ◽  
pp. 783-790 ◽  
Author(s):  
Lynda D. Corkum
Keyword(s):  
Regression Analysis ◽  
Body Size ◽  
Body Length ◽  
Wing Length ◽  
Small Body ◽  
Large Body ◽  
Habitat Type ◽  
Allometric Relationships ◽  
Small Lake ◽  
Rivers And Lakes

AbstractUsing regression analysis on data compiled from the literature, I compared relationships (forewing versus body length) of mayfly imagoes, as a measure of dispersal, between suborders (Schistonota and Pannota) and among habitat type (lotic, lentic, and mixed). There were no significant differences in slopes or intercepts of the regression lines between sexes. Forewing length changed less markedly with body size for species within the ancestral Schistonota than the Pannota. Regression lines for lake and river forms intersect at 7.85 mm (wing length) and 7.30 mm (body length). Small (body length < 7.3 mm) lentic mayflies have proportionately longer wings than small riverine forms. Large (body length > 7.3 mm) riverine mayflies have proportionately longer wings than lentic forms. Based on these relationships, small lake-dwelling mayflies and large riverine mayflies are best able to disperse. Mayfly species occurring in mixed (both rivers and lakes) habitats exhibited allometric relationships similar to mayflies restricted to rivers.

scholarly journals Independent evolution towards larger body size in the distinctive Faroe Island mice

2021 ◽  
Author(s):  
Ricardo Wilches ◽  
William H Beluch ◽  
Ellen McConnell ◽  
Diethard Tautz ◽  
Yingguang Frank Chan
Keyword(s):  
Body Size ◽  
Meta Analysis ◽  
Small Body ◽  
Laboratory Mouse ◽  
Large Body ◽  
Natural Populations ◽  
Size Variation ◽  
Phenotypic Traits ◽  
Island Population ◽  
Multiple Loci

Abstract Most phenotypic traits in nature involve the collective action of many genes. Traits that evolve repeatedly are particularly useful for understanding how selection may act on changing trait values. In mice, large body size has evolved repeatedly on islands and under artificial selection in the laboratory. Identifying the loci and genes involved in this process may shed light on the evolution of complex, polygenic traits. Here, we have mapped the genetic basis of body size variation by making a genetic cross between mice from the Faroe Islands, which are among the largest and most distinctive natural populations of mice in the world, and a laboratory mouse strain selected for small body size, SM/J. Using this F2 intercross of 841 animals, we have identified 111 loci controlling various aspects of body size, weight and growth hormone levels. By comparing against other studies, including the use of a joint meta-analysis, we found that the loci involved in the evolution of large size in the Faroese mice were largely independent from those of a different island population or other laboratory strains. We hypothesize that colonization bottleneck, historical hybridization, or the redundancy between multiple loci have resulted in the Faroese mice achieving an outwardly similar phenotype through a distinct evolutionary path.

scholarly journals Genetic testing of dogs predicts problem behaviors in clinical and nonclinical samples

2020 ◽  
Author(s):  
Isain Zapata ◽  
M. Leanne Lilly ◽  
Meghan E. Herron ◽  
James A. Serpell ◽  
Carlos E. Alvarez
Keyword(s):  
Body Size ◽  
Problem Behaviors ◽  
Small Body ◽  
Community Sample ◽  
Large Body ◽  
Second Phase ◽  
Logistic Regression Models ◽  
Individual Level ◽  
Increased Risk ◽  
Phenotype Data

AbstractVery little is known about the etiology of personality and psychiatric disorders. Because the core neurobiology of many such traits is evolutionarily conserved, dogs present a powerful model. We previously reported genome scans of breed averages of ten traits related to fear, anxiety, aggression and social behavior in multiple cohorts of pedigree dogs. As a second phase of that discovery, here we tested the ability of markers at 13 of those loci to predict canine behavior in a community sample of 397 pedigree and mixed-breed dogs with individual-level genotype and phenotype data. We found support for all markers and loci. By including 122 dogs with veterinary behavioral diagnoses in our cohort, we were able to identify eight loci associated with those diagnoses. Logistic regression models showed subsets of those loci could predict behavioral diagnoses. We corroborated our previous findings that small body size is associated with many problem behaviors and large body size is associated with increased trainability. Children in the home were associated with anxiety traits; illness and other animals in the home with coprophagia; working-dog status with increased energy and separation-related problems; and competitive dogs with increased aggression directed at familiar dogs, but reduced fear directed at humans and unfamiliar dogs. Compared to other dogs, Pit Bull-type dogs were not defined by a set of our markers and were not more aggressive; but they were strongly associated with pulling on the leash. Using severity-threshold models, Pit Bull-type dogs showed reduced risk of owner-directed aggression (75th quantile) and increased risk of dog-directed fear (95th quantile). Our findings have broad utility, including for clinical and breeding purposes, but we caution that thorough understanding is necessary for their interpretation and use.

Alternative Reproductive Tactics

2020 ◽  
pp. 429-446
Author(s):  
Shawn Garner ◽  
Bryan Neff
Keyword(s):  
Body Size ◽  
Small Body ◽  
Large Body ◽  
Morphological Differentiation ◽  
Alternative Reproductive Tactics ◽  
Reproductive Tactics ◽  
Aggressive Interactions ◽  
Single Sex ◽  
Female Mimicry ◽  
Mating Opportunities

Alternative reproductive tactics (ARTs) describe variation among individuals of a single sex in the tactics used to obtain mating opportunities. In crustaceans, ARTs have been observed in multiple taxa and take a variety of forms. ARTs are most commonly observed in males and are generally associated with intense competition among males to monopolize access to breeding females. ARTs frequently involve a guard tactic that competes with other males to monopolize access to females, while a second usurper tactic foregos competition with other males and instead obtains mating opportunities through sneaking behavior. Guard and usurper tactics may be expressed conditionally based on a male’s ability to guard a female (e.g. his body size, the abundance of competitors), or may be expressed as discrete phenotypes that can also include morphological differentiation. For example, in Jassa amphipods the guard tactic is associated with large body size and an enlarged “thumb” on the claw that is used in aggressive interactions with other males, while the usurper tactic is associated with small body size and a reduced thumb. The usurper tactic can take two forms in a marine isopod: small males (gamma) use sneaking behavior to avoid competition with large males (alpha), whereas intermediate-sized males (beta) use female mimicry to avoid competition. Overall, ARTs are well-represented in crustaceans, with many opportunities for continued study to better characterize these unique adaptations.

Description of two new species from Venezuela in the highly diverse dipsadine genus Atractus (Serpentes: Colubridae)

2009 ◽  
Vol 30 (2) ◽  
pp. 233-243 ◽  
Author(s):  
Gilson Rivas Fuenmayor ◽  
Paulo Passos ◽  
Cesar Barrio-Amorós
Keyword(s):  
New Species ◽  
Body Size ◽  
Small Body ◽  
Large Body ◽  
Species Description ◽  
Small Body Size ◽  
Single Female ◽  
Large Body Size ◽  
Body Diameter ◽  
Two New Species

AbstractTwo new species of Atractus are described from Venezuela uplands and highlands on two northern Andean cordilleras. Atractus acheronius, known only from Sierra de Perijá, can be distinguished from congeners by having 17 dorsal scale rows, presence of preocular scales, seven upper and lower labials, seven maxillary teeth, 166 ventrals in the single female, 23 subcaudals, dorsum brown with small dark brown dots, large body size, huge body diameter, and small tail size. Atractus multidentatus, known only from north versant of the Cordillera de Mérida, can be distinguished from congeners by having 17 dorsal scale rows, eight upper and lower labials, 18 maxillary teeth, 153 ventrals in the single female, nine subcaudals, dorsum reddish brown with five longitudinal dark brown stripes, small body size, small body diameter, and small tail size. Additionally, a discussion concerning the species description of Atractus based on unique specimens is provided.

scholarly journals ANALISIS KORELASI DAN REGRESI ANTARA UKURAN-UKURAN TUBUH DENGAN BOBOT BADAN SAPI BRAHMAN CROSS (BX) BETINA DI KPT MAJU SEJAHTERA DESA TRIMULYO, KECAMATAN TANJUNG BINTANG, KABUPATEN LAMPUNG SELATAN

2021 ◽  
Vol 5 (2) ◽  
pp. 99-104
Author(s):  
Obet Yanto ◽  
Muhammad Dima Iqbal Hamdani ◽  
Dian Kurniawati ◽  
Sulastri Sulastri
Keyword(s):  
Body Weight ◽  
Regression Analysis ◽  
Body Size ◽  
Multiple Regression Analysis ◽  
Body Length ◽  
Positive Relationship ◽  
Regression Equation ◽  
Body Measurements ◽  
Body Measurement ◽  
The Relationship

This study aimed to determine the Correlation and the regression equation between body measurements and body weight of Brahman Cross (BX) Cow in KPT Maju Sejahtera Trimulyo village, Tanjung Bintang District, Lampung Selatan Regency. This research was conducted in July 2020. The data obtained were analyzed using simple and multiple regression analysis using the help of the Excel program. The material used in this study were 32 Brahman Cross (BX) Cow aged 2-3 years. The results of this study indicated that the average of Body Weight (BW), Chest Circumference (CC), Body Length (BL), and Shoulder height (SH) were 472.66 � 53.59 kg, 179.95 � 7, 95 cm, 132.49 � 6.39 cm, 127.95 � 3.08 cm, respectively. The correlation value between CC, BL, SH with BB were 0.764, 0.448, and 0.551, respectively. These results indicated that CC, BL, SH, have a positive relationship with BW. The regression equation resulting from the relationship between body weight and body size CC, BL, SH to BW with the value of determination (R2) and significance (P?0.05) was 0.607 (60.7%) with the regression equation BW = -674.003 + 4.314 CC + 1.247 BL + 1.602 SH. Keywords: Brahman Cross, Body Measurement, Correlation and Regression

ASPECTS OF THE BIOLOGY OF FEMALE CHRYSOPS UNIVITTATUS (DIPTERA: TABANIDAE) IN SOUTHWESTERN QUEBEC

1983 ◽  
Vol 115 (4) ◽  
pp. 421-425 ◽  
Author(s):  
D. J. Leprince ◽  
D.J. Lewis
Keyword(s):  
Regression Analysis ◽  
Body Size ◽  
Linear Regression ◽  
Wing Length ◽  
Linear Regression Analysis ◽  
Gonotrophic Cycle ◽  
Dry Ice ◽  
Nectar Feeding

AbstractChrysops univittatus Macquart females were more abundant in late July and early August in southwestern Quebec. Dry-ice baited canopy trap collections consisted of 55% (n = 177) of the nulliparous and 77% (n = 91) of the parous females. Incidence of nectar feeding, as determined by cold anthrone test, was 73% (n = 244) and 96% (n = 268) of the females contained sperm; no difference was found between parous and nulliparous females. This species is anautogenous, and only one gonotrophic cycle was recorded following ovary dissection. Number of ovarioles was correlated with body size (as determined by wing length) by linear regression analysis.

A new species of Sitana (Squamata: Agamidae) from the Deccan Peninsula Biogeographic Zone of India

Zootaxa ◽  
2021 ◽  
Vol 4948 (2) ◽  
pp. 261-274
Author(s):  
V. DEEPAK ◽  
FRANK TILLACK ◽  
NILADRI B. KAR ◽  
VIVEK SARKAR ◽  
PRATYUSH. P. MOHAPATRA
Keyword(s):  
New Species ◽  
Body Size ◽  
Small Body ◽  
Large Body ◽  
Morphological Characters ◽  
Adult Males ◽  
Blue Line ◽  
Dark Blue ◽  
A New Species ◽  
Bright Blue

We describe a new species of fan-throated lizard of the genus Sitana from the Deccan peninsula of India. The new species is from the Sitana sivalensis clade and can be readily diagnosed morphologically from S. sivalensis, S. fusca and S. schleichi by having the dewlap extending beyond forearm insertion. The new species differs from all other congeners in the combination of morphological characters such as a feebly serrated dewlap with a dark blue line on the throat in adult males (versus  a well serrated dewlap with a bright blue patch and orange spots in S. ponticeriana complex), small body size (versus a large body size in S. gokakensis and S. thondalu) and a relatively smaller dewlap size (relatively larger in S. laticeps, S. spinaecephalus, S. dharwarensis, S. gokakensis, S. thondalu, S. marudhamneydhal, S. ponticeriana and S. visiri). The new species was found to be commonly distributed in arid and open habitats as well as in farmlands and plantations in northern Andhra Pradesh, eastern Madhya Pradesh and most parts of Chhattisgarh and Odisha states. 

scholarly journals Zooplankton predators and prey: body size and stable isotope to investigate the pelagic food web in a deep lake (Lake Iseo, Northern Italy)

2016 ◽  
Author(s):  
Barbara Leoni
Keyword(s):  
Body Size ◽  
Stable Isotope ◽  
Body Length ◽  
Trophic Position ◽  
Isotope Analysis ◽  
Large Body ◽  
Zooplankton Community ◽  
Open Water ◽  
Northern Italy ◽  
Food Sources

<p>Seasonal changes in trophic position and food sources of deep subalpine lake (Lake Iseo, Northern Italy) zooplankton taxa were investigated during the year 2011. Furthermore, it's combined carbon and nitrogen Stable Isotope Analysis (SIA) with size-specific analyses of both, the major predatory cladoceran (<em>Leptodora kindtii</em><em>,</em> Focke) and two potential preys (<em>Daphnia</em> <em>longispina</em> complex and <em>Eubosmina longicornis</em>). SIA studies have been extremely useful to track the energy flow through complex trophic network, however, if it is applied to analyze relation between two/few species may lead to misleading interpretations. In fact, integrating size-specificity allowed for understanding why <em>L. kindtii</em> nitrogen isotopic fingerprint fully overlapped with <em>Daphnia</em>, in spring. By investigating changes in <em>L. kindtii</em>'s feeding basket, we found that in spring, <em>L. kindtii </em>mainly relied upon <em>E. longicornis </em>as prey, <em>Daphnia</em> being of too large body size for being captured by <em>L. kindtii.</em> Among preys encountered directly in front by a free-swimming <em>Leptodora</em>, only those able to fit into basket opening can be captured. As basket diameter increases with animal body length, size selection of prey depends on <em>L. kindtii</em> body length. As in other deep, subalpine lakes, <em>E. longicornis </em>was less <sup>15</sup>N-enriched than <em>Daphnia</em>, most likely because of exploiting nitrogen fixing, cyanobacteria colonies, commonly detected in Lake Iseo with the onset of thermal stratification. Cyclopoid adults were at the top of zooplankton food chain and they could potentially be feeding on <em>Daphnia</em>. They, however, likely fed in a different habitat (&gt;20 m deep water), as suggested by a rather than negligible carbon fractionation. The results overall suggest that size-specificity is crucial for addressing space and time changes in trophic links between organisms composing the two hierarchical levels within open water zooplankton community.</p><p> </p>

scholarly journals The size and endocrine activity of the pituitary in mice selected for large or small body-size

1962 ◽  
Vol 3 (3) ◽  
pp. 428-443 ◽  
Author(s):  
R. G. Edwards
Keyword(s):  
Body Weight ◽  
Body Size ◽  
Small Body ◽  
Large Body ◽  
Primary Response ◽  
Endocrine Activity ◽  
Body Weights ◽  
Mouse Pituitary ◽  
Highly Correlated ◽  
Thyroid Secretion

Mice of two strains, N and C, were used in studies on body-size, pituitary size, and endocrine potency of the pituitary. Strain N had been selected for large (NL) and small (NS) body-size; strain C had also been selected for large body-size (CL) but had been crossed to an outbred strain segregating pituitary dwarfism.Pituitary weights and body-weights were highly correlated, the regression lines being common in NL and NS mice. Female pituitaries were considerably heavier than male pituitaries in CL mice. In relation to body-weight, CL pituitaries were consistently heavier than those of NL or NS mice.No differences were detected in the unit potency of gonadotrophins in the pituitaries of NL and NS mice as estimated by the uterine response of immature outbred mice to subcutaneous injections of pituitary tissue. The uptake of 131I into the thyroid was comparable in NL and NS mice per unit of body-weight, and the thyroid secretion rate was also similar using animals of the same body-weight. Immature mice of both lines responded by increased growth to injections of growth hormone or fresh mouse pituitary, though the response was greater in NS than in NL mice.The primary response to selection has probably been in the size of the pituitary rather than in its unit potency. The interrelationships between body-size, body components, organ size and endocrine levels are discussed.

scholarly journals Siphonophoridae from Brazilian Amazonia Part 1 – The genus Columbianum Verhoeff, 1941 (Diplopoda, Siphonophorida)

2018 ◽  
Author(s):  
Helen J. Read ◽  
Henrik Enghoff
Keyword(s):  
New Species ◽  
Body Size ◽  
Small Body ◽  
Large Body ◽  
The Body ◽  
Small Body Size ◽  
Large Body Size ◽  
Small Head ◽  
Three New Species ◽  
Seasonally Flooded

A large sample of Siphonophoridae from Brazil was studied; two morphological groups could be distinguished. Here species considered to be from the genus Columbianum Verhoeff, 1941 are examined in detail. The genus is known from Central and South America (Guatemala, Panama, Honduras, Guiana, Colombia, Peru and Brazil) and is characterised by a clear demarcation between head and rostrum in combination with long antennae, clearly surpassing the tip of the rostrum. A list of previously described species considered to belong to the genus is given; three new species are described: C. major sp. nov. has a large body size and a small head, C. nahvalr sp. nov. has a particularly pronounced domed head and a more castellated appearance to the body, C. adisi sp. nov. has a small body size and a very characteristic hind margin to the pleurites. Variation in the state of preservation of specimens hinders a diagnosis, but the examination of the accessory claw and details of the metazonital limbus and pleurite edges are helpful. Unusually for Diplopoda, the male gonopods are not very useful for identification. Ecological comments are given for each new species, one of which, C. adisi sp. nov., is from the seasonally flooded forest and appears to avoid inundation by climbing trees.

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