scholarly journals What doesn’t kill you makes you stronger: detoxification ability as an honest sexually selected signal

2020 ◽  
Author(s):  
Isaac González-Santoyo ◽  
Daniel González-Tokman ◽  
Miguel Tapia-Rodríguez ◽  
Alex Córdoba-Aguilar
Keyword(s):  
Confocal Microscopy ◽  
Tryptophan Metabolism ◽  
Sexual Signals ◽  
Adult Males ◽  
Sexually Selected Traits ◽  
Individual Survival ◽  
Selected Traits ◽  
Similar Survival ◽  
First Time ◽  
Mating Territories

AbstractSexual selection maintains colourful signals that increase sexual attractiveness and dominance. Some sexually selected, colourful signals are pigments synthesized from ingested amino acids. The underlying metabolic pathways for these pigments often release toxic byproducts that can reduce individual survival. However, rather than discarding these otherwise harmful byproducts, animals may use them by integrating them into sexually selected traits. We tested this idea using males of the damselfly Hetaerina americana, which bear a red-pigmented wing spot that is sexually selected through male-male competition for mating territories. First, by using chromatography and confocal microscopy, we determined that the red wing spots are generated by ommochrome pigments derived from tryptophan metabolism. Second, we injected a group of males with the toxic precursor of these ommochromes, 3-hydroxy-kynurenine (3-Hk), confirming the toxicity of this compound in adult males. Finally, by using spectrophotometry and confocal microscopy, we showed that adult males injected with a LC50 of 3-Hk had more ommochromes in their wing spots than controls but similar survival, suggesting that the deposition of ommochrome pigment in the wing detoxifies the tryptophan metabolism process. Thus, we report for the first time that sexually selected pigmented signals involve the biochemical treatment of excreted compounds that could otherwise have lethal effects, a hypothesis we call “detoxifying ability signalling”. Our results provide new insights about the origin and maintenance of sexual signals, elucidating a mechanism for the evolution of honest indicators of quality that could have arisen due to natural selection.

scholarly journals Experimental evidence for sexual selection against inbred males when it truly counts

2016 ◽  
Author(s):  
Regina Vega-Trejo ◽  
Megan L. Head ◽  
J. Scott Keogh ◽  
Michael D. Jennions
Keyword(s):  
Sexual Selection ◽  
Inbreeding Depression ◽  
Experimental Studies ◽  
Adult Mortality ◽  
Phenotypic Traits ◽  
Adult Males ◽  
Sexually Selected Traits ◽  
Genome Wide ◽  
Unbiased Estimates ◽  
Selected Traits

AbstractAlthough there are many correlational studies, unbiased estimates of inbreeding depression only come from experimental studies that create inbred and outbred individuals. Few such studies determine the extent to which inbreeding depression in males is due to natural or sexual selection. Importantly, traits that are closely related to fitness are predicted to be most strongly affected by inbreeding depression, so measuring fitness or key fitness components, rather than phenotypic traits, is necessary to estimate inbreeding depression accurately. Here, we experimentally created inbred and outbred male mosquitofish (Gambusia holbrooki) by mating full-sibs (f=0.25). We show this led to a 23% reduction in genome-wide heterozygosity. Males were then raised on different diets early in life. We then allowed adult males to compete freely for females to test if inbreeding, early diet, and their interaction affect a male’s share of paternity. Early diet had no effect on paternity, but outbred males sired almost twice as many offspring as inbred males. We also found that males with a relatively long gonopodium (intromittent organ) had greater reproductive success. We demonstrate that inbreeding has important consequences because it negatively affects a key component of male fitness. Given there was no difference in adult mortality this finding can only be due to inbreeding negatively affecting sexually selected traits.

scholarly journals Hide-and-Seek with Tiny Neotenic Beetles in One of the Hottest Biodiversity Hotspots: Towards an Understanding of the Real Diversity of Jurasaidae (Coleoptera: Elateroidea) in the Brazilian Atlantic Forest

Biology ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 420
Author(s):  
Gabriel Biffi ◽  
Simone Policena Rosa ◽  
Robin Kundrata
Keyword(s):  
Atlantic Forest ◽  
Field Research ◽  
Transitional Zone ◽  
Biodiversity Hotspot ◽  
Biodiversity Hotspots ◽  
Brazilian Atlantic Forest ◽  
Life Stages ◽  
Adult Males ◽  
Undescribed Species ◽  
First Time

Jurasaidae are a family of neotenic elateroid beetles which was described recently from the Brazilian Atlantic Forest biodiversity hotspot based on three species in two genera. All life stages live in the soil, including the larviform females, and only adult males are able to fly. Here, we report the discovery of two new species, Jurasai miraculum sp. nov. and J. vanini sp. nov., and a new, morphologically remarkable population of J. digitusdei Rosa et al., 2020. Our discovery sheds further light on the diversity and biogeography of the group. Most species of Jurasaidae are known from the rainforest remnants of the Atlantic Forest, but here for the first time we report a jurasaid species from the relatively drier Atlantic Forest/Caatinga transitional zone. Considering our recent findings, minute body size and cryptic lifestyle of all jurasaids, together with potentially high numbers of yet undescribed species of this family from the Atlantic Forest and possibly also other surrounding ecoregions, we call for both field research in potentially suitable localities as well as for a detailed investigation of a massive amount of already collected but still unprocessed materials deposited in a number of Brazilian institutes, laboratories and collections.

Tests of the positive and functional allometry hypotheses for sexually selected traits in the Jamaican field cricket

2021 ◽  
pp. 104413
Author(s):  
Susan M. Bertram ◽  
Danya D. Yaremchuk ◽  
Mykell L. Reifer ◽  
Amy Villareal ◽  
Matthew J. Muzzatti ◽  
...  
Keyword(s):  
Field Cricket ◽  
Sexually Selected Traits ◽  
Selected Traits

Two new species and taxonomic notes on the Neotropical spiny orb-weaving spi-ders Micrathena and Chaetacis (Araneae: Araneidae), with remarks on the development of Micrathena excavata IVAN L. F. MAGALHÃES & ADALBERTO J. SANTOS (Brazil)

Zootaxa ◽  
2011 ◽  
Vol 2983 (1) ◽  
pp. 39 ◽  
Author(s):  
IVAN L. F. MAGALHÃES ◽  
ADALBERTO J. SANTOS
Keyword(s):  
New Species ◽  
Junior Synonym ◽  
Adult Males ◽  
Development Stages ◽  
Brazilian Amazonia ◽  
Central Brazil ◽  
Adult Females ◽  
Two New Species ◽  
Senior Synonym ◽  
First Time

In this paper, M. yanomami n. sp., from Brazilian Amazonia, Chaetacis bandeirante n. sp., from Central Brazil, and the males of M. gaujoni Simon, 1897 and M. ruschii (Mello-Leitão, 1945) n. comb. , respectively from Ecuador and Brazil, are described and illustrated for the first time. An ontogenetic series of the last development stages of both sexes of Micrathena excavata (C. L. Koch, 1836) is illustrated and briefly described. Adult females are larger and have longer legs and larger abdomens than adult males. Probably females undergo at least one additional moult before adulthood, compared to males. Micrathena ornata Mello-Leitão, 1932 is considered a junior synonym of M. plana (C. L. Koch, 1836), and M. mastonota Mello-Leitão 1940 is synonymized with M. horrida (Taczanowski, 1873). Acrosoma ruschii Mello-Leitão, 1945 is revalidated, transferred to Micrathena and considered a senior synonym of M. cicuta Gonzaga & Santos, 2004. Chaetacis necopinata (Chickering, 1960) is recorded for Brazil for the first time. Chaetacis incisa (Walckenaer, 1841) is considered a nomen dubium.

scholarly journals Sexually Selected Traits: A Fundamental Framework for Studies on Behavioral Epigenetics

ILAR Journal ◽  
2012 ◽  
Vol 53 (3-4) ◽  
pp. 253-269 ◽  
Author(s):  
E. Jasarevic ◽  
D. C. Geary ◽  
C. S. Rosenfeld
Keyword(s):  
Sexually Selected Traits ◽  
Selected Traits

scholarly journals The development of affiliative and coercive reproductive tactics in male chimpanzees

2021 ◽  
Vol 288 (1942) ◽  
pp. 20202679
Author(s):  
Rachna B. Reddy ◽  
Kevin E. Langergraber ◽  
Aaron A. Sandel ◽  
Linda Vigilant ◽  
John C. Mitani
Keyword(s):  
Mating Success ◽  
Sexual Coercion ◽  
Adolescent And Young Adult ◽  
Adolescent Male ◽  
Male Mating ◽  
Adult Males ◽  
Reproductive Tactics ◽  
Males And Females ◽  
First Time ◽  
Older Males

Like many animals, adult male chimpanzees often compete for a limited number of mates. They fight other males as they strive for status that confers reproductive benefits and use aggression to coerce females to mate with them. Nevertheless, small-bodied, socially immature adolescent male chimpanzees, who cannot compete with older males for status nor intimidate females, father offspring. We investigated how they do so through a study of adolescent and young adult males at Ngogo in Kibale National Park, Uganda. Adolescent males mated with nulliparous females and reproduced primarily with these first-time mothers, who are not preferred as mating partners by older males. Two other factors, affiliation and aggression, also influenced mating success. Specifically, the strength of affiliative bonds that males formed with females and the amount of aggression males directed toward females predicted male mating success. The effect of male aggression toward females on mating success increased as males aged, especially when they directed it toward females with whom they shared affiliative bonds. These results mirror sexual coercion in humans, which occurs most often between males and females involved in close, affiliative relationships.

scholarly journals Additions to the species of Dasyhelea KIEFFER, 1911 (Diptera: Ceratopogonidae) from West Bengal, India

2018 ◽  
Vol 87 (4) ◽  
pp. 349-369
Author(s):  
Shubhranil Brahma ◽  
Niladri Hazra
Keyword(s):  
New Species ◽  
West Bengal ◽  
Junior Synonym ◽  
Indian Species ◽  
Palaearctic Species ◽  
Adult Males ◽  
Three New Species ◽  
First Time

Abstract Adult males of three new species, Dasyhelea (Prokempia) barbistyla, Dasyhelea (Pseudoculicoides) pseudohama and D. (Sebessia) scalpra are described from India. The Palaearctic species Dasyhelea (Dasyhelea) pallidiventrisis recorded for the first time from India. Dasyhelea (Ps.) deemingi BOORMAN & HARTEN, 2002 is revised, Dasyhelea (Ps.) acuta BRAHMA, SAHA & HAZRA, 2016 is deemed a junior synonym of Dasyhelea similinigrina NAVAI, 1994, and a key to the Indian species of the subgenera Dasyhelea, Prokempia, Pseudoculicoides and Sebessia is provided.

Characterization of the early development of specific hypaxial muscles from the ventrolateral myotome

Development ◽  
1999 ◽  
Vol 126 (19) ◽  
pp. 4305-4315 ◽  
Author(s):  
Y. Cinnamon ◽  
N. Kahane ◽  
C. Kalcheim
Keyword(s):  
Confocal Microscopy ◽  
Early Development ◽  
Early Generation ◽  
Intercostal Muscles ◽  
Fundamental Component ◽  
Vital Dyes ◽  
First Time ◽  
Second Wave ◽  
Longitudinal Cell

We have previously found that the myotome is formed by a first wave of pioneer cells generated along the medial epithelial somite and a second wave emanating from the dorsomedial lip (DML), rostral and caudal edges of the dermomyotome (Kahane, N., Cinnamon, Y. and Kalcheim, C. (1998a) Mech. Dev. 74, 59–73; Kahane, N., Cinnamon, Y. and Kalcheim, C. (1998b) Development 125, 4259–4271). In this study, we have addressed the development and precise fate of the ventrolateral lip (VLL) in non-limb regions of the axis. To this end, fluorescent vital dyes were iontophoretically injected in the center of the VLL and the translocation of labeled cells was followed by confocal microscopy. VLL-derived cells colonized the ventrolateral portion of the myotome. This occurred following an early longitudinal cell translocation along the medial boundary until reaching the rostral or caudal dermomyotome lips from which fibers emerged into the myotome. Thus, the behavior of VLL cells parallels that of their DML counterparts which colonize the opposite, dorsomedial portion of the myotome. To precisely understand the way the myotome expands, we addressed the early generation of hypaxial intercostal muscles. We found that intercostal muscles were formed by VLL-derived fibers that intermingled with fibers emerging from the ventrolateral aspect of both rostral and caudal edges of the dermomyotome. Notably, hypaxial intercostal muscles also contained pioneer myofibers (first wave) showing for the first time that lateral myotome-derived muscles contain a fundamental component of fibers generated in the medial domain of the somite. In addition, we show that during myotome growth and evolution into muscle, second-wave myofibers progressively intercalate between the pioneer fibers, suggesting a constant mode of myotomal expansion in its dorsomedial to ventrolateral extent. This further suggests that specific hypaxial muscles develop following a consistent ventral expansion of a ‘compound myotome’ into the somatopleure.

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