Some marine invertebrate larvae expand the range of settlement cues to which they will respond as they age. How do relatively simple larvae achieve such complex changes in behaviour? Larvae of the Australian sea urchin Holopneustes purpurascens settle and metamorphose specifically in response to a settlement cue, dissolved histamine, produced by the host alga Delisea pulchra. Older H. purpurasc...

Conflict arises among social organisms when individuals differ in their inclusive-fitness interests. Ant societies are excellent models for understanding how genetic relatedness mediates conflict intensity. However, although conflicts within colonies typically arise over offspring production, the role of larvae as actors in social conflict has received little attention. We develop and empirical...

Data on the morphology of the egg, mature larva (L3) and pupa of Squamapion elongatum (Germar, 1817) are presented. The development cycle of this species lasts 51-54 days: a 12-day egg period, a 30-day larval period, and a 12-day pupal period, on average. The larvae are attacked by parasitic hymenopterans of the superfamily Chalcidoidea.

The growth and development of Helicoverpa armigera was observed in the laboratory by feeding them on different foods viz; leaf, flower and fruit of lady finger, cotton, pigeon pea and chick pea. Based on the food ingested, food digested and food excreted as well as on weight and size of the larvae and the duration of larval period, the fruit of chick pea was found to be the most suitable food f...

Hormonal control of post-embryonic morphogenesis is well established, but it is not clear how differences in developmental endocrinology between species may underlie animal diversity. We studied this issue by comparing metamorphic thyroid hormone (TH) physiology and gonad development across spadefoot toad species divergent in metamorphic rate. Tissue TH content, in vitro tail tip sensitivity to...

Circadian pacemaker neurons contain a molecular clock that oscillates with a period of approximately 24 hr, controlling circadian rhythms of behavior. Pacemaker neurons respond to visual system inputs for clock resetting, but, unlike other neurons, have not been reported to transmit rapid signals to their targets. Here we show that pacemaker neurons are required to mediate a rapid behavior. The...

Temperature controls the rate of fundamental biochemical processes and thereby regulates organismal attributes including development rate and survival. The increase in metabolic rate with temperature explains substantial among-species variation in life-history traits, population dynamics, and ecosystem processes. Temperature can also cause variability in metabolic rate within species. Here, we ...

1. Mosquito samples from the entire life span including senescence were analysed for weight, protein, RNA and DNA. 2. The results for each component indicate that maximal values are attained during larval development. No changes were observed during metamorphosis or the adult period. 3. The peak concentration of RNA and DNA was reached on the third day larval age. Protein content and weight wer...