Life Cycle Tactics and Development

Abstract

As will be shown in the following sections, the fauna of Mediterranean ecosystems is mostly cosmopolitan. Hence, matters concerning plesiotypic life histories (i.e. ancestrally dictated life history patterns) can be investigated in Mediterranean regions. Consideration of life cycle patterns allows for elaboration of the concept of life cycles complying with the seasonality of the Mediterranean climate. The seasonally varying Mediterranean environment by no means implies uniform demographic schedules, as was presumably thought by David (1995). On the contrary, since it involves variables oscillating over large ranges, seasonality forces the pluralistic expression of demographies in accordance with physiological constraints and the evolutionary history of the fauna. The interplay between the need to conform with environmental seasonality on the one hand and historical constraints on the other, determines the way in which patterns are realised in the field. That is the reason why some promising species, such as the white-fringed weevil Graphognathus leucoloma fail to be successful in Mediterranean environments. Matthiessen (1991) claims that this arthropod is poorly adapted to Mediterranean regions probably due to its high demands as to food quality and moisture during reproduction in early summer in conjunction with its relatively high temperature and moisture requirements for larval development and adult emergence in summer. It is obvious that under the constraints of the Mediterranean climate G. leucoloma is unable to realise the patterns dictated by its evolutionary history.