A skeletochronological estimation of age and body size by the Sichuan torrent frog (Amolops mantzorum) between two populations at different altitudes

2010 ◽  
Vol 60 (4) ◽  
pp. 479-489 ◽  
Author(s):  
Xin Lu ◽  
Wen Bo Liao
Keyword(s):  
Body Size ◽  
High Altitude ◽  
Western China ◽  
Population Difference ◽  
Adult Males ◽  
Body Sizes ◽  
Males And Females ◽  
Low Altitude ◽  
Positive Correlations ◽  
Two Populations

AbstractThe age and body size of Amolops mantzorum between two populations distributed in western China were estimated using skeletochronology. The age at sexual mature of individuals was be estimated 2 yrs old in males for both populations while females reached sexual maturity at 2 yrs old at the low-altitude site and 3 yrs old at the high-altitude site. The oldest males and females from the high-altitude site were 7 yrs and 10 yrs old while longevity of males reached 6 yrs and 7 yrs in females at the low-altitude site. Average age between males and females differed significantly at the high-altitude site, but it did no differ significantly at the low-altitude site. For both sexes, average age did not differ significantly between the populations. On average, adult females had significantly larger body sizes than adult males for both populations. Sexual size dimorphism from the low-altitude site and the high-altitude site was 0.280 and 0.282, respectively. Body size between the populations differed significantly within each sex. Positive correlations were found between age and body size for both sexes within each site. The growth coefficient did not differ significantly within a population both sexes or in a sex between the populations. Our findings suggest that inter-population difference in body size of the frogs seems to be related to longevity of individuals, ambient temperature and construction of dams for electricity.

Morphometrics and molecular analysis ofOzolaimus linstowin. sp. (Oxyuroidea: Pharyngodonidae) from the green lizardIguana iguana

2015 ◽  
Vol 90 (2) ◽  
pp. 186-198 ◽  
Author(s):  
S.V. Malysheva
Keyword(s):  
Body Size ◽  
Large Subunit ◽  
Buccal Capsule ◽  
Small Subunit ◽  
Present Species ◽  
Lsu Rdna ◽  
Adult Males ◽  
Spicule Length ◽  
Males And Females ◽  
Characteristic Features

AbstractOzolaimus linstowin. sp. is described from the large intestine ofIguana iguanaLinnaeus, 1758 from Mexico. The present species can be easily distinguished fromO. megatyphlonandO. cirratusby the presence of a long and slender pharynx not divided into sections, more similar to the remaining two species,O. monhysteraandO. ctenosauri. Ozolaimus linstowin. sp. can be differentiated fromO. monhysteraby the shorter spicule length and smaller body size of both males and females. Males ofO. linstowin. sp. are morphologically close to those ofO. ctenosauri, but females possess a markedly smaller body size and differ in the organization of the oral cuticular armature. Adult males ofO. linstowin. sp. bear some characteristic features of the J3 juvenile morphology in terms of the cuticular organization of the oral and buccal capsule. Phylogenetic analysis ofO.linstowin. sp. using partial small subunit (SSU) and D2–D3 large subunit (LSU) rDNA shows relationships with several Oxyuridae genera.

Receiver female body size and distances affect the claw-waving rate of signaller males in fiddler crabs (Brachyura, Ocypodidae)

Behaviour ◽  
2018 ◽  
Vol 155 (10-12) ◽  
pp. 905-914 ◽  
Author(s):  
Fahmida W. Tina ◽  
M. Jaroensutasinee ◽  
K. Jaroensutasinee
Keyword(s):  
Body Size ◽  
Female Body ◽  
Carapace Width ◽  
Fiddler Crabs ◽  
Female Body Size ◽  
Waving Display ◽  
Body Sizes ◽  
Males And Females ◽  
First Time ◽  
Close Distance

Abstract We tested for the first time how Austruca bengali Crane, 1975 signaller males adjusted their waving rates based on receiver female body sizes and their distances. We video recorded the waving display of 46 males (9–12 mm carapace width) for 30 s, and counted their waving rate. Receiver females were categorised as small (8–10 mm carapace width) and large (>10 mm). Distances between males and females were categorised as short (⩽12 cm) and long (>12 cm) distances. Our results indicate that males are able to measure distances and female sizes, and adjust their waving display by actively reducing waving rate (1) towards small females, as usually small females have lower fecundity compared to large ones and (2) towards females at very close distance because at this point, the females would make their mating decision, and thus males start to lead/hit the females towards their burrow rather than waving vigorously.

Differences in skeletal characters between the disjunct eastern and western populations of ring-billed gulls (Larus delawarensis)

1984 ◽  
Vol 62 (6) ◽  
pp. 1067-1074 ◽  
Author(s):  
Beatrice M. Termaat ◽  
John P. Ryder
Keyword(s):  
Discriminant Function ◽  
Multivariate Analyses ◽  
Correct Identification ◽  
Adult Males ◽  
Lake Of The Woods ◽  
Larus Delawarensis ◽  
Males And Females ◽  
Two Populations ◽  
Univariate Analyses ◽  
Discriminant Function Analyses

Univariate analyses of variance, multivariate analyses of variance (Manova), and discriminant function analyses were performed on measurements of 51 skeletal characters of adult males and females from the disjunct eastern and western populations of the ring-billed gull (Larus delawarensis) in Canada. The analyses established sufficient differences in skeletal characters to permit correct identification of the origin of 34 of 38 males (90%) and 40 of 42 females (95%). The populations are now expanding in range to the extent where new colonies are established in the Lake of the Woods, Ontario region, the historical hiatus between the two populations. Further expansion and contact may well erase the existing skeletal differences of individuals in these populations.

Interpopulational variation in sexual dimorphism, reproductive output, and parasitism of Liophis miliaris (Colubridae) in the Atlantic forest of Brazil

2006 ◽  
Vol 27 (1) ◽  
pp. 37-46 ◽  
Author(s):  
Lígia Pizzatto ◽  
Otavio Marques
Keyword(s):  
Body Size ◽  
Sexual Dimorphism ◽  
Atlantic Forest ◽  
Reproductive Output ◽  
Sexual Size Dimorphism ◽  
The Other ◽  
Female Body Size ◽  
Body Sizes ◽  
Northern Atlantic ◽  
Males And Females

AbstractSexual maturity, sexual dimorphism, reproductive output, and parasitism of the colubrid snake Liophis miliaris were compared among populations inhabiting four regions of Brazil: (1) northern coastal Atlantic forest, (2) southern coastal Atlantic forest, (3) northern inland Atlantic forest (4) southern inland Atlantic forest. Females delayed maturity and attained larger body sizes than males in all regions. Males and females from northern Atlantic forest were smaller and attained maturity with a smaller body size than males of other regions. The sexual size dimorphism index ranged from 0.19 to 0.23 and was lowest in the northern Atlantic forest. There was no sexual dimorphism in head length in any of the populations studied. Clutch size was similar in all populations and increased with maternal body size. The reproductive frequency was lower in the northern coastal Atlantic forest and in contrast to the other regions, tended to increase with female body size. The nematoda Ophidiascaris sp. and cystacanths of Oligacanthorynchus spira (Acanthocephala) occurred equally in both sexes. Fewer snakes from the northern coastal Atlantic forest were infested by parasites compared to the other regions and parasitism apparently did not influence reproduction.

scholarly journals Correlates of reproductive success in a population of nine-banded armadillos

1998 ◽  
Vol 76 (10) ◽  
pp. 1815-1821 ◽  
Author(s):  
W J Loughry ◽  
Paulo A Prodöhl ◽  
Colleen M McDonough ◽  
W S Nelson ◽  
John C Avise
Keyword(s):  
Body Size ◽  
Reproductive Success ◽  
The Body ◽  
Birth Date ◽  
Dasypus Novemcinctus ◽  
Male And Female ◽  
Significant Relationships ◽  
Microsatellite Dna Markers ◽  
Body Sizes ◽  
Males And Females

We used microsatellite DNA markers to identify the putative parents of 69 litters of nine-banded armadillos (Dasypus novemcinctus) over 4 years. Male and female parents did not differ in any measure of body size in comparisons with nonparents. However, males observed paired with a female were significantly larger than unpaired males, although paired females were the same size as unpaired females. Females categorized as possibly lactating were significantly larger than females that were either definitely lactating or definitely not lactating. There was no evidence of assortative mating: body-size measurements of mothers were not significantly correlated with those of fathers. Nine-banded armadillos give birth to litters of genetically identical quadruplets. Mothers (but not fathers) of female litters were significantly larger than mothers of male litters, and maternal (but not paternal) body size was positively correlated with the number of surviving young within years, but not cumulatively. There were no differences in dates of birth between male and female litters, nor were there any significant relationships between birth date and maternal body size. Body size of either parent was not correlated with the body sizes of their offspring. Cumulative and yearly reproductive success did not differ between reproductively successful males and females. Average reproductive success (which included apparently unsuccessful individuals) also did not differ between males and females. The majority of adults in the population apparently failed to produce any surviving offspring, and even those that did usually did so in only 1 of the 4 years. This low reproductive success is unexpected, given the rapid and successful range extension of this species throughout the southeastern United States in this century.

scholarly journals Age and body size of Rana amurensis from northeastern China

2011 ◽  
Vol 57 (6) ◽  
pp. 781-784 ◽  
Author(s):  
Wei Chen ◽  
Xin Lu
Keyword(s):  
Body Size ◽  
High Altitude ◽  
Northeastern China ◽  
Life History Strategies ◽  
Male Body ◽  
Age At First Reproduction ◽  
Demographic Traits ◽  
Low Altitude ◽  
Delayed Maturation ◽  
Two Parameters

Abstract Age and body size are two important demographic traits that determine the life history strategies of populations and species. We measured these two parameters of Rana amurensis, at a 900 m and a 500 m altitude site in northeastern China. At the two sites, age at first reproduction was 2 years for males and 3 years for females. The maximum age of males and females at the high-altitude site was 6 and 7 years, and 5 and 7 years at the low-altitude population, respectively. Females were significantly larger than males in both populations, due to greater age in both the highand low-altitude sites. Body size of either males or females did not differ significantly between populations; only males showed increased body size at the high-altitude site when age effect was statistically controlled for. The increased cline of male body size may be attributable to delayed maturation of the sex due to a shorter growing season at high altitudes.

Giant snakes in tropical forests: a field study of the Australian scrub python, Morelia kinghorni

2005 ◽  
Vol 32 (2) ◽  
pp. 193 ◽  
Author(s):  
S. Fearn ◽  
L. Schwarzkopf ◽  
R. Shine
Keyword(s):  
Body Size ◽  
Field Study ◽  
Large Body ◽  
Adult Males ◽  
Heating Rates ◽  
Wet Season ◽  
Ecological Data ◽  
Eastern Australia ◽  
Body Sizes ◽  
Initial Capture

Studies on species that attain very large body sizes provide a powerful opportunity to clarify the ecological correlates and consequences of body size, but logistical obstacles mean that most ‘giant’ species have attracted little field-based research. The Australian scrub python, Morelia kinghorni (= M. amethistina in earlier literature), is the largest Australian snake. Our three-year field study in the Tully River Gorge of tropical north-eastern Australia provides the first detailed ecological data on this species. Snakes aggregate in the gorge during the dry season for reproductive activities (combat, courtship and mating), and these aggregations consist primarily of large adult males. Wet-season samples from a nearby road contained more females, and more juvenile animals. Body temperatures of diurnally active pythons averaged 25.2°C, and were highly correlated with air and substrate temperatures. Larger snakes were cooler than smaller conspecifics, perhaps reflecting their slower heating rates. Recapture of marked individuals suggests that pythons of both sexes and all body sizes maintain fixed home ranges, as the distance from initial capture did not increase through time; most animals were recaptured <100 m from their initial capture point, but some dispersed at least 1.5 km. Adult male pythons spanned a massive range in body sizes (1.3–3.76 m in snout–vent length, 0.30–11 kg in mass), and larger males were more likely to engage in combat, exhibit combat-related injuries (bite wounds) and obtain matings. Presumably reflecting the reproductive advantage of larger body size, males attained much larger maximum sizes than did females within our study population.

scholarly journals Down Feather Structure Varies Between Low- and High-Altitude Torrent Ducks (Merganetta Armata) in the Andes

2017 ◽  
Author(s):  
Rebecca G. Cheek ◽  
Luis Alza ◽  
Kevin G. McCracken
Keyword(s):  
High Altitude ◽  
Environmental Conditions ◽  
Critical Role ◽  
Ambient Temperatures ◽  
The Andes ◽  
Significant Difference ◽  
General Constraints ◽  
Low Altitude ◽  
High Elevations ◽  
Two Populations

AbstractFeathers are one of the defining characteristics of birds and serve a critical role in thermal insulation and physical protection against the environment. Feather structure is known to vary among individuals, and it has been suggested that populations exposed to different environmental conditions may exhibit different patterns in feather structure. We examined both down and contour feathers from two populations of male Torrent Ducks (Merganetta armata) from Lima, Peru, including one high-altitude population from the Chancay-Huaral River at approximately 3500 meters (m) elevation and one low-altitude population from the Chillón River at approximately 1500 m. Down feather structure differed significantly between the two populations. Ducks from the high-altitude population had longer, denser down compared with low-altitude individuals. Contour feather structure varied greatly among individuals but showed no significant difference between populations. These results suggest that the innermost, insulative layer of plumage (the down), may have developed in response to lower ambient temperatures at high elevations. The lack of observable differences in the contour feathers may be due to the general constraints of the waterproofing capability of this outer plumage layer.ResumenEl plumaje es una característica que define a las aves y cumple roles críticos en el aislamiento térmico y protección física del ambiente. Se sabe que la estructura de las plumas varía ente individuos, y se ha sugerido que poblaciones expuestas a diferentes condiciones ambientales pueden exhibir diferentes patrones en la estructura de las plumas. En este estudio se examinaron tanto el plumón como las plumas de contorno de machos adultos del Pato de los Torrentes (Merganetta armata) de dos poblaciones, una en el río Chancay-Huaral a 3,500 msnm y otra en el río Chillón a 1,500 msnm, ubicadas en Lima, Perú. La estructura de los plumones difiere significativamente entre las dos poblaciones. Los patos de la población a grandes elevaciones tienen plumones largos, y densos comparados con los individuos de las partes bajas. La estructura de las plumas de contorno varía ampliamente entre individuos pero no muestra diferencias significativas entre poblaciones. Estos resultados sugieren que las diferencias entre las capas interiores de aislamiento del plumaje (plumón), haberse desarrollado como respuesta en ambientes de bajas temperaturas a grandes elevaciones. En cambio la falta de detectables diferencias en las plumas de contorno puede ser debido a la constante selección en la capacidad impermeable de la capa de plumas exteriores.

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