• Animal cells and systems
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• v.16 no.4
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• pp.337-342
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• 2012

Information about the mating behaviors of an endangered species is critical for the understanding of the natural history of the species as well as in situ and ex situ breeding programs designed to rehabilitate field populations. We describe the mating behaviors of the Mongolian racerunner (Eremias argus), an endangered species in South Korea. The mating of this species consists of precopulatory, copulatory, and postcopulatory stages and is composed of 12 different mating behaviors. During the postcopulatory stage, other males or females not involved in mating show more interference behaviors than during the precopulatory and copulatory stages. The male E. argus has an extraordinarily long postcopulatory bite, which may function as a type of mate-guarding behavior. This study is the first report on the mating behavior of a South Korean reptile.

• International Journal of Industrial Entomology and Biomaterials
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• v.22 no.2
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• pp.51-57
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• 2011

Reproductive activity in the economically important insect, Antheraea mylitta is very important because the female reproduces only once in her life time and the aging is very rapid and costly. It is a capital breeder and strictly a monoandrous species. To know how strategically the insect behaves and the male allocates its ejaculate resource more prudently during its successive mating with virgin females to maximize its own fitness and the fitness of the female with whom it mated, both being most important to sericulture industry. So, the present study was undertaken and the results revealed fresh and virgin females always prefer to mate with fresh virgin males (84%) and receives high dose of ejaculates leading to higher hatchability than to virgin males of one day old (13.7%) and one day old males with mating experience (2.3%). The ejaculation size (as referred to eupyrene sperm count in the ejaculation) declined significantly over successive mating (r = -0.9931, P < 0.001), so also the male body weight (r = -0.9560, P < 0.001). The quantity of ejaculate passed to female also dramatically declined during aging (r = -0.9982, P < 0.001). It was found that male weight contribute substantially to the quantum of ejaculate (r = -0.9519, P < 0.001), so also higher fecund females receive relatively more ejaculate than the lower group to reach higher reproductive fitness. The life time fecundity was found to be $334{\pm}31$.

• Animal cells and systems
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• v.3 no.2
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• pp.167-172
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• 1999

We report for the first time the life history of a 'social' spider, Philoponella prominens, living in a temperate region. Philoponella prominens hibernated as immatures or subadults for 7-8 months in 1995 and 1996 from September-October to April-May in central Korea. When they emerged from their winter hibernation, a majority began their lives as commensals in the webs of other species. As the mating season approached, however, commensal spiders switched to become colonial or solitary. The mating season began in early June and lasted until early August. Newly-hatched spiderlings began to appear in the field in late June. They formed a colony by building their webs connected to the mother's by using pan of the mother's web as supporting substrates. As the season progressed, however, some of the colonial spiderlings became commensal or solitary individuals. Our field observations suggest that Philoponella prominens form colonies or commensal associations to reduce the web-building cost.

• Journal of Aquaculture
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• v.22 no.1
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• pp.16-22
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• 2009

Life history of Korean crayfishes Cambaroides similis (Koelbel) was studied 8 month from March to October, 2006 from the Gwanak mountain, Seoul, South Korea. By capture and recapture method, 551 crayfishes were collected analyzed during the experimental period. Based on the distribution pattern of body lengths, the local population putatively divided into four age groups. The sex ratio of male and female was almost equal. However, their growth rates varied by water temperature. Early juveniles seen during June became adult during August. The study findings suggest that late autumn is mating season.

• Mycobiology
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• v.51 no.6
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• pp.452-462
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• 2023

Opportunistic infections due to Cryptococcus neoformans and C. gattii species complexes continue to rise unabated among HIV/AIDS patients, despite improved antifungal therapies. Here, we collected a total of 20 environmental and 25 presumptive clinical cryptococcal isolates from cerebrospinal fluid (CSF) samples of 175 patients enrolled in an ongoing clinical trial Ambition 1 Project (Botswana-Harvard Partnership). Identity confirmation of the isolates was done using MALDI-TOF MS and PCR. We describe the diversity of the isolates by PCR fingerprinting and sequencing (Oxford Nanopore Technology) of the intergenic spacer region. Mating types of the isolates were determined by amplification of the MAT locus. We report an unusual prevalence of 42.1% of C. neoformans × C. deneoformans hybrids Serotype AD (n = 16), followed by 39.5% of C. neoformans Serotype A (n = 15), 5.3% of C. deneoformans, Serotype D (n = 2), 7.9% of C. gattii (n = 3), and 5.3% of C. tetragattii (n = 2) in 38 representative isolates that have been characterized. Mating type-specific PCR performed on 38 representative environmental and clinical isolates revealed that 16 (42.1%) were MATa/MAT𝛼 hybrids, 17 (44.7%) were MAT𝛼, and five (13.2%) possessed MATa mating type. We used conventional and NGS platforms to demonstrate a potential link between environmental and clinical isolates and lay a foundation to further describe mating patterns/history in Botswana.

• International Journal of Industrial Entomology and Biomaterials
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• v.2 no.2
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• pp.91-105
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• 2001

Taxonomic and phylogenetic studies of firefly in Japan have been reviewed. Fourty-six lampyrid species and one rhagophthalmid are distributed in the Japanese Islands including the Ryukyus. Recently, molecular phylogenetic approaches have been employed in the systematic study of firefly using mitochondrial and luciferase genes. Based on the molecular phylogenetic trees, evolutionary process of flashing patterns related strictly to mating behavior was estimated. Furthermore, genetic diversity studies revealed geographic differentiation patterns within species, and conservation measures of firefly were proposed to protect genetic resources endemic to the localities.

• Animal cells and systems
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• v.16 no.5
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• pp.425-430
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• 2012

The southwestern Australian frog Crinia georgiana (Anura; Myobatrachidae) inhabits ephemeral pools in which the tadpoles often face desiccation. Under these conditions selection on tadpoles can be severe and can directly affect fitness during the aquatic as well as the terrestrial developmental stages. A quantitative genetic study using a half-sib breeding design was conducted to understand the genetic effects on larval life-history traits. We found no significant additive genetic variance in any of larval traits. Except for hatching period, heritability estimates based on females were high in egg size, larval period, snout-vent length, and weight at metamorphosis, suggesting non-additive genetic effects. These results indicate that any response to selection during hatching and larval periods should be predominately governed by non-additive genetic effects in C. georgiana.

• Interdisciplinary Bio Central
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• v.3 no.4
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• pp.13.1-13.8
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• 2011

Previous research has established the existence of individual differences with regards to individuals' optimum time of well-functioning; specifically in terms of being either morning or evening oriented. An association has also emerged between being more evening, as opposed to morning, oriented and having a greater number of sexual partners. The aim of the present study was to investigate whether "eveningness" in males is an evolved sexually dimorphic trait consistent across different cultures. A sample of 179 male Sri Lankan men residing in two different cultural and economic settings, Italy and Sri Lanka, were administered the Morningness-Eveningness Questionnaire (MEQ) followed by assessing their sexual behavior history. The results robustly portrayed a highly significant main effect of MEQ types highlighting the twofold sexual success enjoyed by the evening individuals in both regional locations. Morning oriented individuals, showed a stronger preference for going out and partying than evening-types, suggesting that the higher mating success of evening types is not due to their different lifestyles allowing more opportunities to encounter females. However, evening types exhibited a preference for flirtatious behaviors in the later part of the day. Shoulder-to-hip and handgrip strength, as measures of testosterone levels, were not significantly associated with eveningness. The results are discussed in terms of sexual selection and its interplay with human cultural variation.

• Tribology and Lubricants
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• v.8 no.2
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• pp.14-19
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• 1992

rate of growth of "protective" films of oxides and compounds derived from the lubricant. The protection afforded by the films is strongly dependent on lubricant and steel composition, initial composite surface roughness and the load/speed sequence or history in the early stages of sliding. The protective films, formed by chemical and mechanical action between lubricant and mating surfaces, delayed the surface roughening and offered higher load capacity. Given the great number of variables involved it is not possible to follow more than a few of the chemical changes on surfaces at the end of experiments. Ellipsometry was therefore used to monitor the formation and loss of dual protective films in real time, and also to find the effect of protective films on scuffing and break-in depending on lubricant conditions.

• Korean Journal of Ecology and Environment
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• v.50 no.1
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• pp.116-125
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• 2017

Alpine plants with a scarcity of pollinators in harsh environments have been believed to undergo selfing for reproductive assurance; however, contradictory evidence is also available. Snowmelt regimes in alpine areas function to change life history characteristics of alpine plants such as flowering time and duration; yet the effects of snowmelt regimes have never been tested in alpine plants in Korea. This study was conducted to investigate the dichogamy, mating systems, and flowering characteristics of Megaleranthis saniculifolia populations [early and late snowmelt plots (ESP and LSP, respectively)] in a subalpine area of Sobaeksan Mountain in Korea. M. saniculifolia exhibited incomplete protogyny in that despite early maturation of pistils, maturation times of pistils and stamens within flowers were partly overlapped. Control and hand-outcrossing treatments produced significantly higher number of follicles and seeds per flower than autonomous and hand-selfing treatments. Based on the aggregate fruit set, the auto-fertility index (AI) and self-compatibility index (SI) were 0.33 and 0.50, respectively. Snowmelt occurred 10 days earlier in ESP than in LSP, thereby ESP and LSP showed distinct differences with regard to flower longevity and season, but showing no difference in peak flowering dates. We concluded that M. saniculifolia is an incomplete protogynous and largely outcrossing plant requiring pollinator service. Temporal variation in snowmelt time and subsequent changes in flowering characteristics under climate change may further threaten the population persistence of M. saniculifolia which has already been designated as endangered species in Korea.