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This chapter presents an overview of potential maternal effects on behavioral development, including pre- and postnatal effects of social experiences, stress, and seasonality on the expression of developing phenotypes. It suggests that maternal effects will have a selective advantage when they increase the survival and reproductive success of offspring. This chapter also discusses effects of maternal physiology including gonadal hormones, glucocorticoids and melatonin on offspring phenotype.

This chapter examines the influence of intrauterine position on the behavior of litter-bearing mammals. It reviews evidence that hormones from the mother, from exogenous hormone mimics, and from adjacent fetuses in the uterus can have profound effects on the behavior and physiological development of offspring. This chapter suggests that the intrauterine position of fetuses can have significant developmental consequences because males produce relatively high concentrations of testosterone in the prenatal period that can be transferred either through fetal membranes or the maternal circulation to adjacent siblings. The chapter also discusses the neuroendocrine mechanisms underlying hormone transfer between fetuses.

This chapter describes a wide range of maternal effects on offspring development in fissiped carnivores. It discusses the influence of maternal social rank on offspring status, reproductive development, play behavior, dispersal patterns, and association patterns in spotted hyenas. This chapter also explains the mechanisms underlying these effects which include differential maternal care, nutritional variables, androgenic hormones, insulin-like growth factors, and stress hormones.

This chapter assesses biological control strategies that can reduce turfgrass insect pest populations. Biological control refers to the suppression of pest populations through the activity of living organisms or their by-products. Although a majority of this book is devoted to understanding turfgrass pests, most organisms associated with turfgrass are not pests but instead may be considered beneficial because they reduce thatch, help recycle soil nutrients, or are natural enemies of pest species. Pest outbreaks can sometimes be traced to the absence of natural control agents in the turf environment. Vertebrate and invertebrate predators, insect parasitoids, and microbial pathogens may act as natural enemies of turfgrass pests. Although the effect of one species of natural enemy may be minor, the combined effects of predators, parasitoids, and pathogens can cause considerable reductions in pest populations. Additional agents can be considered as biological controls. These include fungal endophytes (which confer host-plant resistance to some insects), botanicals (botanically derived insecticides), and synthetic compounds that mimic the activity of insect-produced compounds, such as growth hormones and pheromones.