CHAPTER 6
Phenological Patterns
The temporal distribution of arthropod populations is the outcome of a complex process involving both demographic and physiological adaptations (Stamou et al. 1993a). The study of field population dynamics may therefore reveal the way in which evolutionary lineage can be realised under specific conditions, and further hypotheses regarding adaptation can be tested. The
opposite is also possible: hypotheses regarding arthropod life history tactics
and physiological adaptations can be formulated from census data and phenograms. This approach has been deliberately adopted for most Mediterranean
arthropods, so explanations of the synchronisation of their development with
seasonally varying climatic variables can be inferred.
6.1
Modelling Phenological Patterns
In most cases the phenograms of Mediterranean arthropods display asymmetries and discontinuities. For example, the phenogram of the isopod MetaMetaponorthus sp.
:~
>z: 130
>- c
0
E
Qj
0. 100
. .
'0
0
0.
0
.!!l
'0 50
6
c
CI>
Ol
~
>
<{
III
IV
V
XI
XII
II
III
IV
V
Fig. 6.1. Phenogram of the isopod Metaponorthus sp. from northern Israel (Warburg et al. 1984)