Life Cycle Development
71
Table 5.3. Life table for the diplopod G. balcanica dominating in the organic layers at the evergreen-sclerophyllous formation at Hortiatis. (Iatrou and Stamou 1991)
Age structure
nI
1.
mI
1.m.
kValues
Egg
382.00
1.00
1st stage
90.00
0.236
0.63
2nd stage
73.16
0.192
0.36
3rd stage
39.10
0.102
0.27
4th stage
18.11
0.047
0.34
5th-8th stage
4.66
0.012
0.00
9th -11 th stage
4.66
0.012
0.00
12th-l3th stage
4.66
0.012
9.00
0.108
0.00
14th stage
4.66
0.012
l3.80
0.166
0.00
15th stage
4.66
0.012
22.80
0.0.274
0.00
16th stage
4.66
0.012
16.20
0.194
0.00
17th stage
2.67
0.007
19.80
0.139
0.23
18th stage
1.06
0.003
16.20
0.049
0.37
19th stage
0.19
0.0005
12.00
0.006
0.78
R =0.94
fl.. Number of females; II .probability of survival; m.. fecundity
net rate of reproduction results in a value approximating 1 (RO=O.94), which
hardly ensures stable age distribution.
In summing up the above discussion, it can be stated that in comparatively less severe, although strongly fluctuating Mediterranean environments,
periods favourable to energy consuming activities, such as the synthesis and
deposition of eggs and their subsequent development, are short. Hence, relatively few eggs moderately endowed with yolk are rapidly synthesised and
deposited, whereas accumulation of immature specimens (population
reserves) can be recorded in winter due to low heat budgets. Furthermore,
although predictable climatic components dominate over hazardous ones,
animals are capable of overcoming environmental hazards by slight dispersion of oviposition risks over time.
S.3
life Cycle Development
5.3.1
Life Cycle Development of Short-Lived Arthropods
The above conclusions can be exemplified by oribatids from Hortiatis. Figure 5.5, which has been redrawn from original graphs provided by Asikidis
and Stamou (1992), shows the population dynamics of the oribatid Scheloribates cf.latipes. A population dynamics model (Stamou 1986a) was fitted on
71
Table 5.3. Life table for the diplopod G. balcanica dominating in the organic layers at the evergreen-sclerophyllous formation at Hortiatis. (Iatrou and Stamou 1991)
Age structure
nI
1.
mI
1.m.
kValues
Egg
382.00
1.00
1st stage
90.00
0.236
0.63
2nd stage
73.16
0.192
0.36
3rd stage
39.10
0.102
0.27
4th stage
18.11
0.047
0.34
5th-8th stage
4.66
0.012
0.00
9th -11 th stage
4.66
0.012
0.00
12th-l3th stage
4.66
0.012
9.00
0.108
0.00
14th stage
4.66
0.012
l3.80
0.166
0.00
15th stage
4.66
0.012
22.80
0.0.274
0.00
16th stage
4.66
0.012
16.20
0.194
0.00
17th stage
2.67
0.007
19.80
0.139
0.23
18th stage
1.06
0.003
16.20
0.049
0.37
19th stage
0.19
0.0005
12.00
0.006
0.78
R =0.94
fl.. Number of females; II .probability of survival; m.. fecundity
net rate of reproduction results in a value approximating 1 (RO=O.94), which
hardly ensures stable age distribution.
In summing up the above discussion, it can be stated that in comparatively less severe, although strongly fluctuating Mediterranean environments,
periods favourable to energy consuming activities, such as the synthesis and
deposition of eggs and their subsequent development, are short. Hence, relatively few eggs moderately endowed with yolk are rapidly synthesised and
deposited, whereas accumulation of immature specimens (population
reserves) can be recorded in winter due to low heat budgets. Furthermore,
although predictable climatic components dominate over hazardous ones,
animals are capable of overcoming environmental hazards by slight dispersion of oviposition risks over time.
S.3
life Cycle Development
5.3.1
Life Cycle Development of Short-Lived Arthropods
The above conclusions can be exemplified by oribatids from Hortiatis. Figure 5.5, which has been redrawn from original graphs provided by Asikidis
and Stamou (1992), shows the population dynamics of the oribatid Scheloribates cf.latipes. A population dynamics model (Stamou 1986a) was fitted on