CHAPTER 5
Life Cycle Tactics and Development
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.
5.1
life History Characteristics
Key features of the highly heterogeneous Mediterranean environments (e.g.
seasonality of thermal regime, timing of seasonal precipitation, nature of
habitat retreats etc.) appear to have a disproportionate influence on the life
cycle patterns of arthropods in specific cases. For example, Juchault et al.
(1993) found that environment mainly affects reproductive strategies and
reported partly environment-dependent thelygeny in the isopod Armadilli-
Life Cycle Tactics and Development
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.
5.1
life History Characteristics
Key features of the highly heterogeneous Mediterranean environments (e.g.
seasonality of thermal regime, timing of seasonal precipitation, nature of
habitat retreats etc.) appear to have a disproportionate influence on the life
cycle patterns of arthropods in specific cases. For example, Juchault et al.
(1993) found that environment mainly affects reproductive strategies and
reported partly environment-dependent thelygeny in the isopod Armadilli-