scholarly journals Masturbation in a male Phayre's langur, <i>Trachypithecus phayrei</i>

2021 ◽  
Vol 8 (2) ◽  
pp. 43-45
Author(s):  
Md Shalauddin ◽  
Md Jayedul Islam ◽  
Tanvir Ahmed
Keyword(s):  
Social Organization ◽  
Sperm Competition ◽  
Sexual Behaviour ◽  
Reproductive Strategies ◽  
Major Portion ◽  
Evergreen Forest ◽  
Scientific Exploration

Abstract. Masturbation is a common auto-sexual behaviour in humans but is not explicitly known in a major portion of non-human primates. We report the first masturbatory behaviour in a male Phayre's langur, Trachypithecus phayrei, observed in a semi-evergreen forest in northeastern Bangladesh. Like other Asian colobines, the multi-male–multi-female groups of the Phayre's langur suggest a multilevel social organization and a complex hierarchy among males. The lack of sexual opportunity could result in masturbation and sperm competition among males. However, sperm competition is reported to be low in such non-seasonal breeders. Hence, we suggest an adequate characterization of the socio-sexual behaviour and reproductive strategies of this globally endangered primate in order to demonstrate the causes, cost and consequences of masturbation. We also urge further scientific exploration into masturbation among primates due to its evolutionary and conservational significance.

scholarly journals Heparin proteoglycans synthesized by mouse mastocytoma contain chondroitin sulphate

1995 ◽  
Vol 311 (1) ◽  
pp. 233-238 ◽  
Author(s):  
K Lidholt ◽  
I Eriksson ◽  
L Kjellén
Keyword(s):  
Chain Length ◽  
Chondroitin Sulphate ◽  
Major Portion ◽  
Gel Chromatography ◽  
High Affinity ◽  
Polysaccharide Chain ◽  
Polysaccharide Composition ◽  
Length Determination

Proteoglycans (PGs), biosynthetically labelled with [35S]sulphate, were isolated from mouse mastocytoma tissue. Chromatography on antithrombin (AT)-Sepharose resulted in the separation of the 35S-labelled PGs into three fractions: PGs with no affinity for the gel (NA-PGs), PGs with low affinity (LA-PGs), and PGs with high affinity (HA-PGs) for antithrombin. Whereas NA-PGs contained almost exclusively chondroitin sulphate (CS), the AT-binding PGs contained 80-85% heparin and 15-20% CS. [35S]CS-containing macromolecules obtained from the HA-PG fraction after removal of the heparin polysaccharide chains were rechromatographed on AT-Sepharose. A majority of these 35S-labelled macromolecules no longer showed affinity for AT. These experiments indicate that the [35S]CS recovered in the AT-binding PGs is present in hybrid PGs. Polysaccharide chain-length determination demonstrated that the heparin chains were somewhat larger (M(r) approximately 30,000) than the CS chains in the NA-PGs (M(r) approximately 25,000). CS chains in the hybrid PGs were slightly smaller (M(r) approximately 20,000). Characterization of the sulphated CS disaccharides from NA- and HA-PGs showed that they contained similar amounts (20%) of disulphated disaccharides of [GlcA-GalNAc(4,6-di-OSO3)] type. The monosulphated CS-disaccharides were O-sulphated at C-4 of the galactosamine units. Analysis by gel chromatography of the [35S]CS components isolated from HA-PGs after heparinase treatment showed that a major portion of these contained one CS chain only. Calculations of the number of CS and heparin chains in AT-binding PGs, based on polysaccharide composition and polysaccharide chain length, indicate that all heparin-containing PGs are hybrids.

Copulation calls in wild Mueller’s gibbons (Hylobates muelleri)

2019 ◽  
Vol 20 (2) ◽  
pp. 362-374
Author(s):  
Yoichi Inoue ◽  
Waidi Sinun ◽  
Kazuo Okanoya
Keyword(s):  
Mating System ◽  
Social Organization ◽  
Sperm Competition ◽  
Mate Guarding ◽  
Conservation Area ◽  
Mating Activity ◽  
Selective Pressures ◽  
Female Promiscuity ◽  
Vocal Signals ◽  
The Relationship

Abstract Mating activity of a wild Mueller’s gibbon group (Hylobates muelleri) was observed in the Danum Valley Conservation Area, Sabah, Malaysia. The purpose of this study was to investigate the function of copulation calls in gibbons. The female emitted copulation calls at the time of intromission and pelvic thrusting. Copulation calls were composed of two notes and one of them was sung only while mating. Approximately half of copulation calls were sung near the range boundary. Mating with copulation calls sometimes occurred while singing. According to the model that female copulation calls have evolved under the selective pressures of risk of infanticide and sperm competition, copulation calls should be rare in species with little female promiscuity. As gibbons usually live in pair-living social organization and have a monogamous mating system, no vocal signals by female gibbons are considered to be needed. However, clear copulation calls were emitted by the female. It suggests that the relationship between paired gibbons is unstable. Copulation calls by the female Mueller’s gibbon may function to increase mate guarding and strengthen the pair bond.

scholarly journals Wolbachia infection reduces sperm competitive ability in an insect

2006 ◽  
Vol 273 (1593) ◽  
pp. 1455-1458 ◽  
Author(s):  
Fleur E Champion de Crespigny ◽  
Nina Wedell
Keyword(s):  
Population Dynamics ◽  
Sperm Competition ◽  
Empirical Evidence ◽  
Reproductive Strategies ◽  
Competitive Ability ◽  
Cytoplasmic Incompatibility ◽  
Wolbachia Infection ◽  
Sperm Production ◽  
Fitness Costs ◽  
Wolbachia Pipientis

The maternally inherited bacterium Wolbachia pipientis imposes significant fitness costs on its hosts. One such cost is decreased sperm production resulting in reduced fertility of male Drosophila simulans infected with cytoplasmic incompatibility (CI) inducing Wolbachia . We tested the hypothesis that Wolbachia infection affects sperm competitive ability and found that Wolbachia infection is indeed associated with reduced success in sperm competition in non-virgin males. In the second male role, infected males sired 71% of the offspring whereas uninfected males sired 82% of offspring. This is the first empirical evidence indicating that Wolbachia infection deleteriously affects sperm competition and raises the possibility that polyandrous females can utilize differential sperm competitive ability to bias the paternity of broods and avoid the selfish manipulations of Wolbachia . This suggests a relationship between Wolbachia infection and host reproductive strategies. These findings also have important consequences for Wolbachia population dynamics because the transmission advantage of Wolbachia is likely to be undermined by sperm competition.

Expression and characterization of recombinant human factor V and a mutant lacking a major portion of the connecting region

Biochemistry ◽  
1990 ◽  
Vol 29 (29) ◽  
pp. 6762-6768 ◽  
Author(s):  
William H. Kane ◽  
Denise Devore-Carter ◽  
Thomas L. Ortel
Keyword(s):  
Human Factor ◽  
Major Portion ◽  
Factor V

Attachment and sexual strategies

2009 ◽  
Vol 32 (1) ◽  
pp. 43-44
Author(s):  
Lane E. Volpe ◽  
Robert A. Barton
Keyword(s):  
Mate Choice ◽  
Sexual Behaviour ◽  
Reproductive Strategies ◽  
Life Histories ◽  
Sexual Strategies ◽  
Intervening Variables

AbstractSexual behaviour and mate choice are key intervening variables between attachment and life histories. We propose a set of predictions relating attachment, reproductive strategies, and mate choice criteria.

scholarly journals Subcellular Distribution of 51Cr and Characterization of its Binding Sites in Human Platelets

Blood ◽  
1970 ◽  
Vol 35 (5) ◽  
pp. 727-739 ◽  
Author(s):  
MANFRED STEINER ◽  
MARIO G. BALDINI
Keyword(s):  
Binding Sites ◽  
Cell Damage ◽  
Human Platelets ◽  
Major Portion ◽  
Minor Role ◽  
Ionic Form ◽  
Sodium Chromate ◽  
Cytoplasmic Fraction ◽  
Mitochondrial Fractions

Abstract Subcellular fractionation of human platelets labeled with radioactive sodium chromate was utilized to study distribution and characterization of the 51Cr binding sites in these cells. The cytoplasmic fraction of the platelets contained the major portion of the radioactivity while microsomal and mitochondrial fractions played a minor role in the binding of chromate. The stromal sediment had approximately one third of the total radioactivity. Only about 20 per cent of the 51Cr taken up by the platelets was in a free ionic form and was in the cytoplasmic fraction. The major portion of the 51Cr in the platelets was bound to nucleotides in the platelet cytoplasm. Nucleotides of the α-granules had no radioactive chromate. Hypertonic media and platelet antiserum produced marked release of 51Cr from the platelets, whereas aggregating agents produced none. In physiologic conditions, elution of 51Cr from labeled platelets is very limited because there is only little 51Cr in free ionic form in the cells. Release of considerable amount of 51Cr from the platelets can occur only in case of cell damage with release of nucleotides from the cytoplasmic pool. This was seen with hypertonic solutions and with platelet antibody. Platelet degranulation, as it occurs with aggregating agents, is not associated with release of 51Cr since the granular pool of nucleotides is not labeled by this compound.

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