• 제목/요약/키워드: Egg color dimorphism

검색결과 4건 처리시간 0.023초

Effect of Host Egg Color Dimorphism on Interactions Between the Vinous-throated Parrotbill (Paradoxornis webbianus) and Common Cuckoo (Cuculus canorus)

  • Yoo, Jeong-Chil;Lee, Jin-Won
    • Animal cells and systems
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    • 제8권2호
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    • pp.77-80
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    • 2004
  • To investigate the effect of host egg color dimorphism on the vinous-throated parrotbill (Paradoxornis webbianus) - common cuckoo (Cuculus canorus) interactions, we monitored breeding nests of vinous-throated parrotbills, and conducted model egg experiments, using two colors: white and blue. Of the 190 nests examined in this study, cuckoo parasitism occurred at 10 nests (8 blue and 2 white egg clutches, respectively), and only blue cuckoo eggs were found. This frequency was similar to the egg-color ratio of all host nests found (151 blue and 39 white egg clutches). Vinous-throated parrotbills showed high rejection rate towards both cuckoo eggs and model ones. There was a significant difference in rejection rates towards mimetic (blue) and non-mimetic (white) eggs in blue egg clutches. Mimetic eggs put in nests took significantly longer to be rejected than non-mimetic ones. The most common rejection method used by the hosts was egg ejection (puncture-ejection). The costs of ejecting non-mimetic eggs tended to be lower than those of ejecting mimetic eggs. These results indicate that egg-color dimorphism in this species favors the individuals having white egg clutches in terms of higher rejection rate and lower ejection costs of the parasitic eggs. This study also suggests that egg-color dimorphism of the vinous-throated parrotbill decreases the effect of cuckoo parasitism on host populations.

Egg Rejection by Both Male and Female Vinous-throated Parrotbills Paradoxornis webbianus

  • Lee, Jin-Won;Kim, Dong-Won;Yoo, Jeong-Chil
    • Animal cells and systems
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    • 제9권4호
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    • pp.211-213
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    • 2005
  • In bird species that suffer brood parasitism, the question about which sex is responsible for egg rejection has important implications for determining the coevolutionary relationship between brood parasites and their hosts. In order to determine which sex rejects a parasitic egg in vinous-throated parrotbills (Paradoxornis webbianus) which have egg color dimorphism, we conducted model egg experiments and video-recorded the behavior of the focal pair. Both sexes showed rejection behavior to the parasitic eggs. It indicates that the vinous-throated parrotbill may have a high rejection rate and faster spread of any rejection alleles through out populations. However, further studies are still needed to confirm the egg recognition mechanism in this species, which will expand our knowledge of the evolutionary relationship between host and parasite.

줄종개 Cobitis tetralineata (Pisces; Cobitidae)의 개체군 생태 (Population Ecology of Korean Sand Loach Cobitis tetralineata (Pisces; Cobitidae) in the Seomjin River, Korea)

  • 김익수;고명훈;박종영
    • Journal of Ecology and Environment
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    • 제29권3호
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    • pp.277-286
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    • 2006
  • 줄종개, Cobitis tetralineata의 생태를 섬진강 지류인 추령천에서 조사하였다. C. tetralineata는 하상이 모래이고, 유속이 $10{\sim}20cm/see$, 수심은 $30{\sim}150cm$인 곳에 대부분 서식하였다. 활동은 낮에만 활동하는 주행성 어류로 3월부터 10월까지 활동하였고, 이후 11월부터 이듬해 2월까지는 바닥 속으로 파고들어가 월동하였다. 성비는 암컷과 수컷이 1 : 0.57로 나타났고, 암컷이 수컷보다 $20{\sim}30mm$(TL)이 더 컸다. 줄종개(암컷)의 연령은 $20{\sim}40mm$가 당년생, $45{\sim}65mm$가 1년생, $65{\sim}90mm$가 2년생, 90 mm 이상이 3년생 이상으로 추정되었다. 부화 후 $13{\sim}14$개월 이후에 수컷 가슴지느러미 제2기조에 골질반이 형성되어 암수가 구별되었으며, 또한 수컷은 산란시기에 반문변 이가 일어났다. 산란시기는 수온이 $22{\sim}26^{\circ}C$인 6월 말부터 7월 중순으로 추정되었고, 포란수는 $1,288{\pm}583(474{\sim}2,976)$개, 난경은 $0.98{\pm}0.1mm$이었다. 섭식은 주로 깔다구류, 꽃병벌레류, 물벼룩류, 조류 등을 섭식하였으며, 섭식률은 4월과 9월에 높게 나타났고 월동기에는 섭식하지 않았다.