A compendium of original articles and review papers comprising of 21 chapters, bifurcated into two sections in the area of animal ecology and reproduction. Section I provides a glimpse into the recent research on nematodes ecology; ecological adaptation in bugs; fish diseases; reviews on pollutional and ecological problems of diverse aquatic habitats. It also includes a chapter on the ecology and natural history of Indian crocodiles and an account on the population dynamics and status of peafowl in some habitats of India. Section II on animal reproduction gives an insight into current research on the reproductive potential of diverse animals ranging from insects through mammals and also reviews the progress made in the field in the past few years. An account of prey-feed modulation and reproductive potential of freshwater emydid turtles and a review of the hypothalamic pituitary gonadal axis in animals emphasizes the relationship between organism and their immediate environment.