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Metamorphosis is an obligatory feature in insect physiology mediating to insect evolution, wherein the individual acquires characteristic adult features and stops molting during postembryonic development. Ecdysteroids and juvenile hormones (JHs) are key hormones that are responsible for insect molting and metamorphosis contributing in this process for successful adaptation. To understand the development process of insects, this paper reviews the mechanisms of the major hormones, especially how they control the insect metamorphosis process and their control over gene expression for stage speciation. It also focuses on the source of synthesis of those hormones, their active signalling pathway. This paper is supported by secondary information. According to the literature reviewed, ecdysteroids and Juvenile Hormones (JHs) are key hormones that are responsible for insect molting and metamorphosis, respectively. JH maintains the larval state and its decline along with the increase of ecdysteroid in the hemolymph are crucial to elicit transformation to the pupal stage; therefore, the precise control of JH and Ecdysteroid (ecdysone & 20E), is necessary for normal development and the initiation of metamorphosis. Juvenile hormone signalling pathway with referring to Kr-h1, BR-C and E93 genes have also been described.

The Lesser Crested Tern (Thalasseus bengalensis emigratus) breeding population in the Mediterranean is found exclusively in Libya, on the two coastal islands of Gara and Elba and one wetland on the mainland coast at Benghazi. In order to improve knowledge of the species migration to wintering quarters in West Africa, a ringing programme was initiated in 2006 and continued until 2012. From a total of 1354 nestlings ringed using metal and/or colour rings, 64 were recovered along their flyway and in their wintering range, representing 6.90% of birds ringed with both colour and metal rings. This provided the opportunity to collect information on post-natal movements (staging and wintering ranges), breeding philopatry and recruitment, in addition to a preliminary estimation of their migration journey duration. This paper indicates

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