Is there a trade-off between the melanin allocated to the immune system and to camouflage on larvae of the dragonfly Micrathyria catenata Calvert,1909 (Odonata: Libellulidae)?



Document title: Is there a trade-off between the melanin allocated to the immune system and to camouflage on larvae of the dragonfly Micrathyria catenata Calvert,1909 (Odonata: Libellulidae)?
Journal: Neotropical : biology and conservation
Database: PERIÓDICA
System number: 000410730
ISSN: 1809-9939
Authors: 1
2
Institutions: 1Universidade de Brasilia, Instituto de Ciencias Biologicas, Brasilia, Distrito Federal. Brasil
2Universidade Federal de Goias, Instituto de Ciencias Biologicas, Goiania, Goias. Brasil
Year:
Season: Sep-Dic
Volumen: 4
Number: 3
Pages: 133-136
Country: Brasil
Language: Inglés
Document type: Nota breve o noticia
Approach: Analítico, descriptivo
English abstract In insects, the immune system responds to the presence of antigens involving them in melanin. However, the melanin is also allocated into the exoskeleton’s pigmentation, used to camouflage. We aimed to test the existence of a trade-off between the allocation of melanin to the immune system and to camouflage on the larvae of Micrathyria catenata. We conducted the study in the “Reserva do km 41” (41 km’ Reserve), 80 km distant from Manaus, Amazonas, Brazil. We implanted a nylon line into the abdomen of 30 larvae and observed if had or not deposition of melanin in the line. We counted the number of individuals who responded to implant depositing melanin and, later, we took photos of the larvae’s heads and calculate gray intensity. We used a t-test for independent samples. 76% of larvae responded to treatment depositing melanin on the implants. There were no significant differences in the intensity of gray between the larvae that responded to the implants and those who did not responded. There is no trade-off to allocation of melanin for camouflage and for the immune system. This should happen because the immune system is not limited by the acquisition of resources or the camouflage’s demand for melanin is not enough to influence the immune system
Portuguese abstract Em insetos, o sistema imunológico responde à presença de antígenos encapsulandoos com melanina. Porém a melanina também é alocada no exoesqueleto para pigmentação, promovendo a camufl agem. Objetivamos testar se existe uma demanda conflitante entre alocar melanina para o sistema imunológico e para a camuflagem nas larvas de Micrathyria catenata. Realizamos o estudo na Reserva do km 41, a 80 km de Manaus, Amazonas. Inserimos um implante de nylon no abdome de 30 larvas e observamos se houve ou não deposição de melanina. Contamos os indivíduos que responderam ao implante depositando melanina. Posteriormente, fotografamos as cabeças das larvas e calculamos a intensidade de cinza. Usamos um teste t para amostras independentes. 76% das larvas responderam ao tratamento depositando melanina nos implantes. Não houve diferença signifi cativa na intensidade de cinza entre as larvas que responderam aos implantes e as que não responderam. Não encontramos uma demanda confl itante na alocação de melanina para a camuflagem e para o sistema imunológico. Isso pode ser devido ao fato de o sistema imunológico não ser limitado pela aquisição de recursos ou de a camufl agem não demandar melanina sufi ciente para infl uenciar o sistema imune
Disciplines: Biología
Keyword: Inmunología,
Insectos,
Libélulas,
Camuflaje,
Sistema inmune,
Micrathyria catenata,
Compensación
Keyword: Biology,
Immunology,
Insects,
Dragonflies,
Camouflage,
Immune system,
Micrathyria catenata,
Trade-off
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