scholarly journals Anuran forelimb muscle tendinous structures and their relationship with locomotor modes and habitat use

2018 ◽  
Vol 65 (5) ◽  
pp. 599-608 ◽  
Author(s):  
Silvia De Oliveira-Lagôa ◽  
Félix B Cruz ◽  
Débora L Moreno Azócar ◽  
Esteban O Lavilla ◽  
Virginia Abdala

Abstract The interaction between organisms and their environment is central in functional morphology. Differences in habitat usage may imply divergent morphology of locomotor systems; thus, detecting which morphological traits are conservative across lineages and which ones vary under environmental pressure is important in evolutionary studies. We studied internal and external morphology in 28 species of Neotropical anurans. Our aim was to determine if internal morphology (muscle and tendons) shows lower phylogenetic signal than external morphology. In addition, we wanted to know if morphology varies in relation to the habitat use and if there are different functional groups. We found differences in the degree of phylogenetic signal on the groups of traits. Interestingly, postaxial regions of the forelimb are evolutionarily more labile than the preaxial regions. Phylomorphospace plots show that arboreal (jumpers and graspers) and swimmer frogs cluster based on length of fingers and the lack of sesamoid, also reflected by the use of habitat. These functional clusters are also related to phylogeny. Sesamoid and flexor plate dimensions together with digit tendons showed to be important to discriminate functional groups as well as use of habitat classification. Our results allow us to identify a “grasping syndrome” in the hand of these frogs, where palmar sesamoid and flexor plate are absent and a third metacarpal with a bony knob are typical. Thus, a lighter skeleton, long fingers and a prensile hand may be key for arboreality.

2018 ◽  
Vol 5 (5) ◽  
pp. 172470 ◽  
Author(s):  
Stephanie K. Courtney Jones ◽  
Adam J. Munn ◽  
Phillip G. Byrne

Captive breeding programmes are increasingly relied upon for threatened species management. Changes in morphology can occur in captivity, often with unknown consequences for reintroductions. Few studies have examined the morphological changes that occur in captive animals compared with wild animals. Further, the effect of multiple generations being maintained in captivity, and the potential effects of captivity on sexual dimorphism remain poorly understood. We compared external and internal morphology of captive and wild animals using house mouse ( Mus musculus ) as a model species. In addition, we looked at morphology across two captive generations, and compared morphology between sexes. We found no statistically significant differences in external morphology, but after one generation in captivity there was evidence for a shift in the internal morphology of captive-reared mice; captive-reared mice (two generations bred) had lighter combined kidney and spleen masses compared with wild-caught mice. Sexual dimorphism was maintained in captivity. Our findings demonstrate that captive breeding can alter internal morphology. Given that these morphological changes may impact organismal functioning and viability following release, further investigation is warranted. If the morphological change is shown to be maladaptive, these changes would have significant implications for captive-source populations that are used for reintroduction, including reduced survivorship.


2019 ◽  
Vol 28 (2) ◽  
pp. 167-176
Author(s):  
Mohammad Shamimul Alam ◽  
Md Nazmul Hoque ◽  
Mousumi Akter ◽  
Reza Md Shahjahan

Samples of Drosophila species were collected from some selected sites (viz., Dohar Upazila of Dhaka Division, Hironpoint of the Sundarbans, Satchori of Sylhet Division) of Bangladesh and these were cultured in the laboratory to study developmental stages, external morphological traits and sex comb. They were identified as D. melanogaster, D. ananassae and D. bipectinata. The sex comb teeth number and arrangement were distinct for all three species. D. melanogaster had one row of 10 - 11 teeth in the sex comb. D. ananassae had eight rows of teeth in the sex comb possessing 32 - 33 teeth in total. D. bipectinata had 2 - 3 rows of teeth in the sex comb and total teeth number varied from 11 to 15. Among three species, sex comb teeth number of D. bipectinata varied most. Eleven different patterns (n=20) in sex comb were observed in D. bipectinata indicating significant diversity within species. Variation in pupation sites among three species was also observed in the laboratory condition. D. bipectinata pupated on the food medium, whereas other two species pupated on the vial wall. Thus, diversity among these three species of Drosophila was documented which could be utilized as bioindicator in future. Dhaka Univ. J. Biol. Sci. 28(2): 167-176, 2019 (July)


Zootaxa ◽  
2008 ◽  
Vol 1939 (1) ◽  
pp. 58-60 ◽  
Author(s):  
DIRK ERPENBECK ◽  
OLIVER VOIGT ◽  
MEHMET GÜLTAS ◽  
GERT WÖRHEIDE

Unravelling the phylogenetic relationships of sponges (Phylum Porifera) is an important as well as challenging task. It helps the understanding of character evolution among early branching metazoans but also aids in bioprospecting for valuable bioactive sponge compounds. However, the phylogenetic relationships among Porifera are largely unsolved, because the simple poriferan bauplan frequently prevents unambiguous taxonomic species assignment and a clear definition of morphological synapomorphies is difficult (see e.g. Boury-Esnault 2006). DNA sequence markers are frequently employed to overcome morphological shortcomings in phylogeny (e.g. Kelly Borges et al. 1991) and taxonomy (e.g. DNA barcoding, see Wörheide & Erpenbeck 2007). However, some DNA markers suffer from insufficient phylogenetic signal (see e.g. Duran et al. 2004 and Wörheide 2006 on CO1 in population studies) and unequal evolutionary rates among taxa (see e.g. Erpenbeck et al. 2004 on 28S in Haplosclerida). Therefore, a careful evaluation and selection of molecular markers for each individual project is required.


2020 ◽  
Vol 13 (4) ◽  
pp. 413-422
Author(s):  
Ichiro Tamaki ◽  
Yae Yamada

Abstract Aims In a contact zone between related taxa, phenotypic variation can result from genetic and/or environmental gradients. This study aimed to clarify the cause of phenotypic variation in leaf morphology of two Quercus crispula varieties—crispula (QCC) and mongolicoides (QCM)—in their contact zone along an altitudinal gradient. Methods We measured 6 morphological traits of leaves and recorded genotypes of 13 nuclear microsatellite loci for 48 individuals in the contact zone and 24 individuals in each of the reference populations of QCC and QCM. We constructed a model explaining the phenotypic variation (leaf morphology) in relation to environmental (altitude) and genetic (ancestry from the reference population) gradients. Important Findings Both morphological and genetic markers distinguished the two varieties in the reference populations well. We were able to confirm the power of both morphological and genetic markers. Individuals within the contact zone population had intermediate ancestry that was slightly biased to QCM ancestry, and the distribution of their morphologies overlapped with those of the two varieties in the reference populations. The effect of altitude on leaf morphological traits was significant, while that of ancestry was not. Distributions of ancestry and interclass heterozygosity in the contact zone population resembled those in F2 or later generation hybrids. These results indicate that in the contact zone between QCC and QCM, there is no ongoing hybridization, but environmental pressure has created an altitudinal gradient in morphological traits through phenotypic plasticity and/or variation in functional genes.


2019 ◽  
Author(s):  
Y.M. Lozano ◽  
C.A. Aguilar-Trigueros ◽  
I.C. Flaig ◽  
M.C. Rillig

ABSTRACTDrought can strongly modify plant diversity and ecosystem processes. As droughts are expected to intensify in the future, it is important to better understand plant responses to drought. We expect that roots traits constitute an overlooked but powerful predictor of plant responses as roots are in direct contact with the soil environment, taking up nutrients and water.Here, we determine which root traits are sensitive to drought, the magnitude of that response, whether their predictive power and relationships with shoot biomass are affected by drought and whether all these responses depend on plant functional group. To do so, we conducted a glasshouse experiment with 24 plant species grown in pots (10 replicates per species), which represent three different functional groups: grasses, herbs and legumes. All replicates were well watered during the first month and then half of the replicates were kept under drought (30 % water holding capacity (WHC)) with the other half serving as control (kept at 70% WHC). After two months of the treatment, leaf and root traits were measured.Leaf traits had a strong but more uniform response to drought compared to root traits. Root trait response was variable and differed by plant functional group. Most grasses had increased root diameter, specific root surface area (SRSA) while decreased root tissue density (RTD) with drought. Production of thicker roots with a low tissue density could allow grasses to achieve greater nutrient and water acquisition through mycotrophy and would be linked to an increase in the reserve of non-structural carbohydrates needed for osmoregulation. Herbs had decreased SRSA and specific root length (SRL) while increase root carbon allocation. Reduction of root elongation or sacrifice of fine roots would be compensated by an increase in root carbon allocation, which allow herbs to improve water uptake. Legumes did not alter root morphological traits but promote an early flowering in order to scape drought.Our results identify changes in root morphological traits as mechanisms to likely face drought, a response that is species-specific and differed among functional groups.


Author(s):  
F. Leasi ◽  
M.A. Todaro

During a survey of the marine meiobenthos in a predominantly muddy area, 40 km south of Venice (northern Adriatic Sea, Italy), 11 species of gastrotrichs were recorded. Gastrotrichs were found in 11 out of the 16 investigated stations, with densities (mean ± standard deviation) ranging from 0.6 ± 0.5 to 97.7 ± 71.2 ind./10 cm2. The community was dominated by Musellifer profundus, which made up 24.5% of the entire gastrotrich assemblage and reached in a single station the abundance peak of 18.3 ind./10 cm2. The finding bears relevance to the biogeography and ecology of several species. The presence of numerous specimens of the rare M. profundus allowed new insights into the arrangement and functioning of the hermaphroditic sexual apparatus in this phylogenetically important genus, for which such data are scanty. The new information will certainly be useful in evolutionary studies aimed at reconstructing the phylogenetic relationships within Gastrotricha, while offering at the same time additional morphological traits to be used in reliable species identification. Although only three species of Musellifer have been described so far, there are several others awaiting a formal affiliation, a task that will benefit from this new information.


2020 ◽  
Vol 129 (3) ◽  
pp. 652-663 ◽  
Author(s):  
Juan D Carvajal-Castro ◽  
Yelenny López-Aguirre ◽  
Ana María Ospina-L ◽  
Juan C Santos ◽  
Bibiana Rojas ◽  
...  

Abstract The evolution and diversification of animal reproductive modes have been pivotal questions in behavioural ecology. Amphibians present the highest diversity of reproductive modes among vertebrates, involving various behavioural, physiological and morphological traits. One such feature is the amplexus, which is the clasp or embrace of males on females during reproduction and is found almost universally in anurans. Hypotheses about the origin of amplexus are limited and have not been tested thoroughly, nor have they taken into account evolutionary relationships in most comparative studies. However, these considerations are crucial to an understanding of the evolution of reproductive modes. Here, using an evolutionary framework, we reconstruct the ancestral state of amplexus in 685 anuran species. We investigate whether the type of amplexus has a strong phylogenetic signal and test whether sexual size dimorphism could have influenced amplexus type or male performance while clasping females. Overall, we found evidence of ≥34 evolutionary transitions in amplexus type across anurans. We found that amplexus type exhibits a high phylogenetic signal and that amplexus type does not evolve in association with sexual size dimorphism. We discuss the implications of our findings for the diversity of amplexus types across anurans.


2014 ◽  
Vol 57 (1) ◽  
pp. 1-16 ◽  
Author(s):  
Ana González ◽  
Manuel Luque ◽  
Mariano Herrera ◽  
Carlos González ◽  
Elena Angón ◽  
...  

Abstract. The aim of this study was to determine whether the classification of local Spanish breeds of dogs, based on morphological traits, matches or differs from the classification based on the dogs' breeding goals. A total of 15 biometric measurements and 10 functional indices were obtained in 1 365 dogs (709 females and 656 males). The dogs we measured belonged to 16 different breeds, 14 of which were officially recognized by the Spanish Royal Canine Society. Similar average values of morphometric traits and indices (P<0.001) were obtained in both sexes: the Ratonero Bodeguero Andaluz was the breed with the smallest format and the Pyrenean and Spanish Mastiff, the largest. In the case of the Fédération Cynologique Internationale (FCI) groups, significant differences (P<0.001) for morphometric traits were found, and in both sexes, the third group was the one with the smallest format and the second group, the largest. The differences obtained were more marked between all groups than within groups, and the morphological characteristics were similar, in accordance with the purpose for which the breeds were bred. Therefore, the existence of a morphologic pattern is accepted both in the breeds and the functional groups. Two as yet officially unrecognized breeds, the Orito and Paternino Hound, must be included in the fifth and the first FCI groups, respectively. When the Orito Hound is recognized, it will be added to the fifth FCI group and the word »hound« will be deleted from the name Paternino breed.


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