Reproductive behavior and parental roles of the cichlid fish Laetacara araguaiae

We described the reproductive behavior of the small South American cichlid Laetacara araguaiae in streams from Brazil. We predicted that this species will show reproductive cooperation and division of labor between males and females in a similar way presented by other substrate-spawner cichlids. Thus, we studied 34 pairs in the pre-spawning (n = 11), egg/wriggler (n = 11) and fry (n = 12) phases. In the pre-spawning phase both sexes become involved in nest building and territorial defense, but females emphasizes building nest (p = 0.03), while males invest more time in territorial defense (p = 0.04). After spawning, male and female alternate between rearing eggs and defending nest in the territory. In the egg/wriggler phase females devotes more time rearing the brood while males remain defending territory (p = 0.02). These differences disappear when young are in the fry stage, and parents jointly stay closer to fry (p = 0.98). However, at this phase, there is a reduction in the frequency of threats shown by males (p<0.01) and an increase in the frequency of attacks shown by female (p<0.01) that could be a response to an increased demand for parental defense. Our results indicate that the reproductive cooperation between males and females of L. araguaiae is marked by division of labor in the early reproductive phases and by sharing of parental duties as brood develops.

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Differences in male and female cognitive abilities: Sexual selection or division of labor?

Behavioral and Brain Sciences ◽

10.1017/s0140525x00042503 ◽

1996 ◽

Vol 19 (2) ◽

pp. 254-255

Author(s):

Michael T. Ghiselin

Keyword(s):

Sexual Selection ◽

Natural Selection ◽

Sexual Dimorphism ◽

Division Of Labor ◽

Cognitive Abilities ◽

Reproductive Competition ◽

Male And Female ◽

Males And Females

AbstractIn Darwinian terminology, “sexual selection” refers to purely reproductive competition and is conceptually distinct from natural selection as it affects reproduction generally. As natural selection may favor the evolution of sexual dimorphism by virtue of the division of labor between males and females, this possibility needs to be taken very seriously.

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THE SECONDARY SEX CHARACTERS AND REPRODUCTIVE BEHAVIOR OF GONADECTOMIZED STICKLEBACKS TREATED WITH METHYL TESTOSTERONE

Canadian Journal of Zoology ◽

10.1139/z63-034 ◽

1963 ◽

Vol 41 (4) ◽

pp. 611-628 ◽

Cited By ~ 63

Author(s):

Evelyn Hui Wai ◽

William S. Hoar

Keyword(s):

Reproductive Behavior ◽

Body Cavity ◽

The Body ◽

Combined Effects ◽

Male And Female ◽

Long Day ◽

Building Behavior ◽

Males And Females ◽

Secondary Sex Characters ◽

Behavior Characteristic

Treatment of intact juvenile or gonadectomized adult male and female stickle-backs with methyl testosterone, either by immersion in dilute solutions or by implantation of pellets into the body cavity, induces male secondary sex characters. The effect, as quantified by measurements of the height of the brush border tubules in the mesonephros, is the same in both sexes and reaches a maximum in 3 to 4 weeks. Both the gonadectomized males and females develop prespawning aggressive and territorial behavior if maintained 4 or 5 weeks under long-day photoperiods (16-hour day alternating with 8-hour darkness). Such behavior does not appear under a short photoperiod. The administration of methyl testosterone does not intensify aggressive behavior in either the 8-hour or 16-hour photoperiod fish. The combined effects of long photoperiods and methyl testosterone induces nest-building behavior (characteristic of normal breeding males) in 50% to 60% of the castrated males and about 6% of the gonadectomized females. The behavior of the treated males is qualitatively and quantitatively similar to naturally matured fish but that of the females shows differences. Although male sexual behavior may also be induced in androgen treated castrates it has not been observed in the females under comparable experimental procedures.

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Male and female cichlid fish show cognitive inhibitory control ability

Scientific Reports ◽

10.1038/s41598-019-52384-2 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 3

Author(s):

Manuela Lombardi Brandão ◽

Ana Marina Tabah de Almeida Fernandes ◽

Eliane Gonçalves-de-Freitas

Keyword(s):

Inhibitory Control ◽

Cognitive Flexibility ◽

Nile Tilapia ◽

Food Reward ◽

Cichlid Fish ◽

Male And Female ◽

Inhibitory Ability ◽

Spawning Site ◽

Transparent Barrier ◽

Males And Females

Abstract Inhibitory control is a way to infer cognitive flexibility in animals by inhibiting a behavioral propensity to obtain a reward. Here we tested whether there are differences in inhibitory control between females and males of the fish Nile tilapia owing to their distinct reproductive roles. Individuals were tested under a detour-reaching paradigm, consisting of training fish to feed behind an opaque barrier and, thereafter, testing them with a transparent one. Fish is expected to avoid trying to cross through the transparent barrier to achieve food (reward), thus showing inhibitory control by recovering the learned detour with the opaque apparatus. Both males and females learned to detour the transparent barrier with similar scores of correct responses, whereas females reached the food faster. This result is probably associated to their different sex roles in reproduction: females care for the eggs and fry inside their mouth (thus requiring a high inhibitory control not to swallow them), whereas males have to stay inside the territory defending it against intruder males, which also demands some inhibitory ability not to leave the spawning site and take the risk of losing it. Furthermore, this evidence of cognitive flexibility can enable social fish to deal with unpredictable interactions.

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(3S,6E)-Nerolidol-mediated rendezvous of Cyclocephalini beetles, Cyclocephala paraguayensis, in bottle gourd flowers

10.1101/2020.06.09.142059 ◽

2020 ◽

Author(s):

Arodí P. Favaris ◽

Amanda C. Túler ◽

Weliton D. Silva ◽

Sérgio R. Rodrigues ◽

Walter S. Leal ◽

...

Keyword(s):

Reproductive Behavior ◽

Essential Role ◽

Floral Scent ◽

Bottle Gourd ◽

Major Constituent ◽

Gut Content ◽

Male And Female ◽

Sesquiterpene Alcohol ◽

Males And Females ◽

Airborne Volatiles

AbstractCyclocephalini beetles of genus Cyclocephala (Coleoptera: Melolonthidae: Dynastinae) use flowers of some plants as food, shelter, and mating stands. However, little is known about floral scent chemistry involved in this interaction. Here we show that a sesquiterpene alcohol mediates attraction of Cyclocephala paraguayensis Arrow on bottle gourd flowers, Lagenaria siceraria (Curcubitaceae). Both males and females started to aggregate on flowers at twilight; after that, mating began and remained for the entire night. The major constituent of the airborne volatiles from L. siceraria was fully characterized as (3S,6E)-nerolidol, which elicited electroantennographic responses on male and female antennae. Field bioassays showed that traps baited with the natural stereoisomer or a mix of nerolidol isomers captured significantly more males and females of C. paraguayensis than control traps. Analysis from the gut content of these Cyclocephalini beetles showed the presence of pollen, suggesting that they also use bottle gourd flowers for their nourishment. Taken together, these results suggest that (3S,6E)-nerolidol plays an essential role in the reproductive behavior of C. paraguayensis by eliciting aggregation, mating, and feeding.

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Convict cichlid parents that stay with the same mate develop unique and consistent divisions of roles

PeerJ ◽

10.7717/peerj.10534 ◽

2020 ◽

Vol 8 ◽

pp. e10534

Author(s):

Jennifer L. Snekser ◽

Murray Itzkowitz

Keyword(s):

Division Of Labor ◽

Cichlid Fish ◽

Direct Care ◽

Biparental Care ◽

Convict Cichlid ◽

Offspring Survival ◽

Parental Roles ◽

Convict Cichlids ◽

Amatitlania Nigrofasciata ◽

Over Time

Previous studies, largely on avian species, have suggested that pairs that are permanently monogamous and have biparental care develop a coordination over time that enhances offspring survival. If this is the case, we predicted that a parent involved in biparental care would develop a pattern of biparental care specific to a particular mate and remain consistent in that pattern over time but would lose this pattern if it were to change mates. We tested this prediction with the convict cichlid fish (Amatitlania nigrofasciata) which has biparental care that is both complex and flexible. In this species, each parent can perform all parental roles but typically shows a division of labor in which males typically defend against offspring predators while the female typically provides direct care to the offspring. At various times, the parents briefly switch roles. Our experiments revealed that pairs that remained together for two consecutive broods were more consistent in their parental behaviors, including time they spent near the intruder and in the nest compared to pairs that were comprised of individuals that had previously mated with other partners. Also individuals that remained with the same partner were also more consistent as a parental unit, maintaining their sex-specific roles of males defending aggressively against an intruder and females spending more time directly caring for young. While our experiment clearly support our prediction that individuals do develop unique coordination with specific individuals, convict cichlids in nature appear to be largely serially monogamous in which they mate only once before changing partners. Thus, it is likely this coordination may be available in many species that have biparental care but become adaptive when repeated matings become common.

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Parental roles and mating system in the black-winged stilt

Canadian Journal of Zoology ◽

10.1139/z03-082 ◽

2003 ◽

Vol 81 (6) ◽

pp. 947-953 ◽

Cited By ~ 5

Author(s):

J J Cuervo

Keyword(s):

Reproductive Success ◽

Parental Care ◽

Mating System ◽

Parental Investment ◽

Mate Guarding ◽

Egg Laying ◽

Nest Building ◽

Fertile Period ◽

Parental Roles ◽

Males And Females

The breeding behaviour of black-winged stilts (Himantopus himantopus) was studied in southwestern Spain. In the prelaying period males devoted more time than females to agonistic encounters, locomotion, and nest building. During egg laying, males spent more time than females at the nest, mostly building the nest and covering the eggs, while females spent more time foraging than males. During late incubation, females spent significantly more time at the nest than males. These results suggest very similar parental investment by the sexes. During part of the female's fertile period, males stayed at the nest while females were foraging, which precluded efficient mate guarding. However, females were reluctant to engage in extra-pair copulations, being always very aggressive towards conspecifics except for their mates. Even in two cases of extra-pair copulation, the first described for this species, the female continuously attacked the intrusive male and did not cooperate in copulation. Male parental care seems to be essential for reproductive success and females are probably faithful in order to assure male parental investment. The need for parental care from both males and females would maintain social, and perhaps also genetic, monogamy in this species.

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GONADOTROPHIN PATTERNS IN MALE AND FEMALE RATS:

Acta Endocrinologica ◽

10.1530/acta.0.0580600 ◽

1968 ◽

Vol 58 (4) ◽

pp. 600-612 ◽

Cited By ~ 1

Author(s):

Robert Boyd ◽

Donald C. Johnson

Keyword(s):

Ascorbic Acid ◽

Testosterone Propionate ◽

Female Rats ◽

Female Rat ◽

Feedback Effects ◽

Male And Female ◽

Prostate Weight ◽

Male And Female Rats ◽

Males And Females ◽

Normal Males

ABSTRACT The effects of various doses of testosterone propionate (TP) upon the release of luteinizing hormone (LH or ICSH) from the hypophysis of a gonadectomized male or female rat were compared. Prostate weight in hypophysectomized male parabiotic partners was used to evaluate the quantity of circulating LH. Hypophyseal LH was measured by the ovarian ascorbic acid depletion method. Males castrated when 45 days old secreted significantly more LH and had three times the amount of pituitary LH as ovariectomized females. Administration of 25 μg TP daily reduced the amount of LH in the plasma, and increased the amount in the pituitary gland, in both sexes. Treatment with 50 μg caused a further reduction in plasma LH in males, but not in females, while pituitary levels in both were equal to that of their respective controls. LH fell to the same low level in partners of males or females receiving 100 μg TP. When gonadectomized at 39 days, males and females had the same amount of plasma LH, but males had more stored hormone. Pituitary levels were unchanged from controls following treatment with 12.5, 25 or 50 μg TP daily, but plasma values dropped an equal amount in both sexes with the latter two doses. Androgenized males or females, gonadectomized when 39 days old, were very sensitive to the effects of TP and plasma LH was significantly reduced with 12.5 μg daily. Pituitary LH in androgenized males was higher than that of normal males but was reduced to normal by small amounts of TP. The amount of stored LH in androgenized females was not different from that of normal females and it was unchanged by any dose of TP tested. Results are consistent with the conclusion that the male hypothalamic-hypophyseal axis is at least as sensitive as the female axis to the negative feedback effects of TP. Androgenization increases the sensitivity to TP in both males and females.

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Gender Differences in Clothing Worn in Current Popular Comic Books

MacEwan University Student eJournal ◽

10.31542/j.muse.186 ◽

2015 ◽

Vol 2 (1) ◽

Author(s):

Kyle Landon Jossy

Keyword(s):

Gender Differences ◽

Content Analysis ◽

Comic Books ◽

Book Industry ◽

Comic Book ◽

Lower Body ◽

Female Characters ◽

Male And Female ◽

Males And Females

This study looked at how males and females were portrayed, based on the amount of skin shown in the clothing worn. A Content analysis was performed on a sample of 20 randomly selected popular comics from the last 3 years. Both male and female characters were rated on how much skin they showed in three clothing categories; neck line, sleeve length, and lower body. Results showed that in all 3 categories, women consistently wore more revealing clothing. The findings demonstraetd that the comic book industry is comparable to other forms of media, in the sexualization of female characters, by having them wear more revealing clothing.

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Reproductive behavior

10.1093/oso/9780198797500.003.0013 ◽

2018 ◽

Cited By ~ 1

Author(s):

Rachel Olzer ◽

Rebecca L. Ehrlich ◽

Justa L. Heinen-Kay ◽

Jessie Tanner ◽

Marlene Zuk

Keyword(s):

Sexual Selection ◽

Sexual Conflict ◽

Female Choice ◽

Reproductive Behavior ◽

Mating Systems ◽

Insect Behavior ◽

Sequential Approach ◽

Evolutionary Mechanisms ◽

Anatomy And Physiology ◽

Males And Females

Sex and reproduction lie at the heart of studies of insect behavior. We begin by providing a brief overview of insect anatomy and physiology, followed by an introduction to the overarching themes of parental investment, sexual selection, and mating systems. We then take a sequential approach to illustrate the diversity of phenomena and concepts behind insect reproductive behavior from pre-copulatory mate signalling through copulatory sperm transfer, mating positions, and sexual conflict, to post-copulatory sperm competition, and cryptic female choice. We provide an overview of the evolutionary mechanisms driving reproductive behavior. These events are linked by the economic defendability of mates or resources, and how these are allocated in each sex. Under the framework of economic defendability, the reader can better understand how sexual antagonistic behaviors arise as the result of competing optimal fitness strategies between males and females.

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Spinal Muscular Atrophy after Nusinersen Therapy: Improved Physiology in Pediatric Patients with No Significant Change in Urine, Serum, and Liquor 1H-NMR Metabolomes in Comparison to an Age-Matched, Healthy Cohort

Metabolites ◽

10.3390/metabo11040206 ◽

2021 ◽

Vol 11 (4) ◽

pp. 206

Author(s):

Leon Deutsch ◽

Damjan Osredkar ◽

Janez Plavec ◽

Blaž Stres

Keyword(s):

Machine Learning ◽

Spinal Muscular Atrophy ◽

1H Nmr ◽

Pediatric Patients ◽

Muscular Atrophy ◽

Male And Female ◽

Before And After ◽

Healthy Cohort ◽

Males And Females ◽

Urine Serum

Spinal muscular atrophy (SMA) is a genetically heterogeneous group of rare neuromuscular diseases and was until recently the most common genetic cause of death in children. The effects of 2-month nusinersen therapy on urine, serum, and liquor 1H-NMR metabolomes in SMA males and females were not explored yet, especially not in comparison to the urine 1H-NMR metabolomes of matching male and female cohorts. In this prospective, single-centered study, urine, serum, and liquor samples were collected from 25 male and female pediatric patients with SMA before and after 2 months of nusinersen therapy and urine samples from a matching healthy cohort (n = 125). Nusinersen intrathecal application was the first therapy for the treatment of SMA by the Food and Drug Administration (FDA) and the European Medicines Agency (EMA). Metabolomes were analyzed using targeted metabolomics utilizing 600 MHz 1H-NMR, parametric and nonparametric multivariate statistical analyses, machine learning, and modeling. Medical assessment before and after nusinersen therapy showed significant improvements of movement, posture, and strength according to various medical tests. No significant differences were found in metabolomes before and after nusinersen therapy in urine, serum, and liquor samples using an ensemble of statistical and machine learning approaches. In comparison to a healthy cohort, 1H-NMR metabolomes of SMA patients contained a reduced number and concentration of urine metabolites and differed significantly between males and females as well. Significantly larger data scatter was observed for SMA patients in comparison to matched healthy controls. Machine learning confirmed urinary creatinine as the most significant, distinguishing SMA patients from the healthy cohort. The positive effects of nusinersen therapy clearly preceded or took place devoid of significant rearrangements in the 1H-NMR metabolomic makeup of serum, urine, and liquor. Urine creatinine was successful at distinguishing SMA patients from the matched healthy cohort, which is a simple systemic novelty linking creatinine and SMA to the physiology of inactivity and diabetes, and it facilitates the monitoring of SMA disease in pediatric patients through non-invasive urine collection.

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