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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2010.03.014 Byline: Jared G. Ali (a), Douglas W. Tallamy (b) Abstract: Using spotted cucumber beetles and their epicuticular hydrocarbon signatures, we examined two hypotheses about how females may use signals that describe a potential mate's immune system to identify high-quality males. Females may find males to be acceptable mates when (1) a male's immune system complements or matches the immune system of the receptive female (immunocompatibility), or (2) a male successfully signals that it has a strong immune system (immunocompetence). The first experiment used gas chromatography to compare the epicuticular hydrocarbon signature of a female beetle with that of a male she rejected and a male she accepted as a mate. We also compared the hydrocarbon signatures of a male and two fertilized females, one that had voluntarily accepted his spermatophore and one that was forced to accept the spermatophore. In both experiments the immune response to an implant inserted in the insect's abdomen was compared in males and their offspring. The hydrocarbon signature of males accepted as mates in the first experiment differed more from that of their female partners than did the hydrocarbon signature of rejected males. There was no significant difference in the immune response of accepted and rejected males. Offspring from forced matings had significantly lower immune responses than offspring from voluntary matings. This study suggests that females use immunocompatibility rather than immunocompetence as a trait to identify quality mates, which fosters stronger immune systems in offspring. Female choice of mates in this species may be self-referenced using the cuticular hydrocarbon signature of the female as a standard. Author Affiliation: (a) Department of Entomology & Nematology, University of Florida, U.S.A. (b) Department of Entomology & Wildlife Ecology, University of Delaware, U.S.A. Article History: Received 4 May 2009; Revised 22 June 2009; Accepted 12 March 2010 Article Note: (miscellaneous) MS. number: A09-00286

An investigation is conducted into the sexual selection of arthropods and the development of paternal care by reducing paternity assurance and increasing promiscuity of males. The results support the theory that in arthropods, certain male behaviours are traits on which sexual selection has acted.

It is difficult to predict maternal care among insects since a number of factors have shaped its development. Maternal care may involve low costs, as in the case of the horsefly. Some insects can breed more than once in a season, and these insects have more to lose by investing in maternal care, since the number of offspring that they can produce is limited. Mothers have greater freedom to invest in offspring if this does not prevent them from breeding again.

A study was conducted to examine whether a chemical deposited by the female lace bug, Gargaphia solani Heidemann, during or shortly after oviposition is a signal for egg dumping. Results showed that egg dumping was more frequent when exposed to chemical extracts from young egg masses and was not stimulated by visual cues. Moreover, the ovipositional chemical used by egg-dumpers is not a way of relocating their eggs.

1. With evidence of significant global insect declines mounting, urgent calls to mitigate such declines are also increasing. Efforts to reverse insect declines will only succeed, however, if we correctly identify and address their major causes. 2. One potential cause that has received little mention is the global spread of non‐native plants as invasive species, agroforestry products, and ornamental plants. 3. Here we (a) review the theory predicting that most insect herbivores are evolutionarily constrained to use a fraction of available plant lineages; (b) document the extent to which nonnative plants have displaced native plant communities around the globe; (c) examine the evidence that non‐native plants reduce insect abundance and diversity; and (d) suggest guidelines for measuring the impact of non‐native plants on insect populations. 4. We conclude that host range expansions to non‐natives do occur among many insect herbivores but not at the frequency required to prevent insect declines when non‐native plants replace native plant communities. Accordingly, we suggest that curbing the spread and use of non‐ native plants at local, national, and international scales will be a necessary and effective way to reduce some insect declines. [ABSTRACT FROM AUTHOR]