I have a paper in the May issue of Ethology entitled ‘Ontogenetic changes in web design in two orb-web spiders’. Note that there is a mistake in the affiliation (due to a misunderstanding the address was changed by the journal during production). Although it says University of Oxford, the work was actually done while I was a postdoc at the Smithsonian Tropical Research Institute.
Hesselberg, T. (2010). Ontogenetic changes in web design in two orb-web spiders. Ethology 116: 535-545.
The paper can be accessed here if you have an institutional licence. If not you are welcome to contact me for a copy.
Abstract
The first orb web built by newly hatched spiders resembles the adult web in its overall form and structure. However, many details show ontogenetic changes. One possible explanation for these changes is that the tiny early-instar spiders with their minute brains will make more mistakes and build less ‘perfect’ orb webs than older and larger juveniles and adults. To test this hypothesis, known as the size limitation hypothesis, I analysed orb webs from three developmental stages, spiderlings, juveniles and adult females, in two neotropical orb-web spiders, the araneid Eustala illicita and the nephilid Nephila clavipes. Neither species showed clear signs of being behaviourally limited or more prone to committing errors as spiderlings than were older juveniles or adults. These findings therefore do not support the size limitation hypothesis in either species. Finally, I looked for evidence of the ‘biogenetic law’, which predicts that juveniles should build less derived orb webs than the adults. Evidence for this was found in E. illicita, but not in N. clavipes.
Resumen
La primera telaraña orbicular construida por arañas recién salidas del huevo se parece a la tela de una araña adulta en su forma general y estructura. Sin embargo, muchos detalles muestran cambios genéticos. Una posible explicación para estos cambios es que las diminutas arañas con sus pequeños cerebros tendrían mayores errores y construirían telarañas orbiculares menos “perfectas” que arañas jóvenes y adultas, más viejas y largas. Para probar esta hipótesis, conocida como la hipótesis de limitación de tamaño, analice telarañas orbiculares de tres etapas de desarrollo, bebe, jóvenes y hembras adultas; en dos arañas orbiculares neo-tropicales, la araneid Eustala illicita y la nephilid Nephila clavipes. Ninguna especie mostro signos claros de conducta limitada o mas prono a cometer errores cuando bebe que cuando son jóvenes mayores o adultos. Estos resultados por lo tanto no apoyan la hipótesis de limitación de tamaño en cualquier especie. Por último, busque evidencia de la “la ley de biogenética”, que predice que las jóvenes deberían construir menos derivadas telarañas orbiculares que los adultos. Evidencia de lo anterior fue encontrada en E. illicita, pero no en N. clavipes.
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