Among insects, perhaps the most appreciated are those that are esthetically pleasing: few capture the interest of the public as much as vibrantly colored dragonflies and damselflies (Insecta: Odonata). These remarkable insects are also extensively studied. Here, we review the history of odonate systematics, with an emphasis on discrepancies among studies. Over the past century,…
In a recent paper D.R. Paulson (2004; IJO 7: 505-515) presented five hypotheses concerning the way wings are held in the Zygoptera during perching. A critical examination suggests that most of them have substantial flaws that prevent their testing. Based on Bechly’s phylogeny (1998;
Comparative investigations of the distal part of the vesica spermalis (‘glans’) of the anisopteran male secondary copulatory apparatus reveal three different ‘solutions’ of combining the emptying-mechanism of the sperm-reservoir with a ‘washing out’ of sperm of the male predecessor. The responsible apparatus of the glans—actually driven by pressure-changes inside the erectile organ, which is a…
We compiled data on the occurrence and frequency of distinct female variants among Holarctic Odonata and interpreted the data in light of harassment-based hypotheses. The major source of male confusion for male mimicry hypotheses is predicted to be signal similarity between andromorphs and male distractors; for the learned mate recognition hypothesis (LMR), it is predicted…
The functional morphology of the male caudal clasping apparatus of Zygoptera is compared to that of Epiophlebia superstes (Anisozygoptera) and Anisoptera. Hypotheses concerning the mechanics and muscle functions have been advanced by parallel construction of mechanical working models. The evolution of the clasping apparatus and the tandem linkage shifting – from the female pronotum to…
Disjunct biogeographic patterns of similar species remain enigmatic within evolutionary biology. Disparate distributions typically reflect species responses to major historical events including past climate change, tectonics, dispersal, and local extinction.
The evolution of sibling cannibalism as a maternal strategy is particularly challenging to explain when nurseries are shared among multiple females. Such is the case for the damselfly, Megaloprepus caerulatus, whose females lay eggs in bark above the water line in large, water-filled tree holes.
Environmental management is one of the most important activities in ecological conservation at present. Faced with various socioeconomic impacts (e.g., urbanization, agriculture, and logging), practical and effective ways to analyze and determine how biodiversity is affected by these anthropogenic activities are essential.
In sexual conflict, males are often thought to gain fitness benefits from harassing females over mating. Yet when harassment itself incurs costs to males and if alternative, receptive females are available in a local population, theory predicts that when confronted with a female refusal, a male’s choice of persisting or retreating is determined in part by the likelihood of achieving a mating.
The matrix, an environment in the landscape that individuals move through but do not reside in, can affect species dispersal and the arrival of individuals at habitat patches. Elements around this matrix that provide refuge or resources may shape the arrival of animals at habitat patches, even when those patches are equivalent in quality. Adult dragonflies (Odonata: Anisoptera) frequently use open terrestrial environments during movement and dispersal in north-temperate regions…