Table 1.
Values of the main egg parameters and their incubation periods for four pairwise cuckoo–host species comparisons.
| Parameters | Cuckoo | Host |
|---|---|---|
| Comparison 1 | Common cuckoo (Cuculus canorus) n = 21 | Great reed warbler (Acrocephalus arundinaceus) n = 21 |
| Egg volume, V (cm3) | 3.3 | 3.0 |
| Egg surface area, S (cm2) | 10.9 | 10.3 |
| S/V (cm2/cm3) | 3.3a | 3.5a |
| T/S (μm/cm2) | 8.9a | 8.0a |
| Estimated incubation period according to Eqn (6), I (days) | 13.6a | 15.0a |
| Standard average incubation period for host eggs according to Planet of Birds (2011) |
14 |
|
| Comparison 2 | Common cuckoo (Cuculus canorus) n = 1 | European robin (Erithacus rubecula) n = 1 |
| Egg volume, V (cm3) | 2.4 | 2.3 |
| Egg surface area, S (cm2) | 8.8 | 8.5 |
| S/V (cm2/cm3) | 3.7 | 3.7 |
| T/S (μm/cm2) | 10.2 | 9.4 |
| Estimated incubation period according to Eqn (6), I (days) | 12.0 | 12.9 |
| Standard average incubation period for host eggs according to Bouglouan (2024) |
13 |
|
| Comparison 3 | Plaintive cuckoo (Cacomantis merulinus) n = 4 | Rufescent prinia (Prinia rufescens) n = 8 |
| Egg volume, V (cm3) | 1.7a | 1.3a |
| Egg surface area, S (cm2) | 7.0a | 5.8a |
| S/V (cm2/cm3) | 4.1a | 4.6a |
| T/S (μm/cm2) | 11.4 | 10.9 |
| Estimated incubation period according to Eqn (6), I (days) | 10.8 | 11.3 |
| Standard average incubation period for host eggs according to Krishnan (2021) |
12 |
|
| Comparison 4 | Plaintive cuckoo (Cacomantis merulinus) n = 2 | Common tailorbird (Orthotomus sutorius) n = 2 |
| Egg volume, V (cm3) | 1.6 | 1.1 |
| Egg surface area, S (cm2) | 6.7 | 5.3 |
| S/V (cm2/cm3) | 4.3 | 4.8 |
| T/S (μm/cm2) | 12.0 | 10.7 |
| Estimated incubation period according to Eqn (6), I (days) | 10.3 | 11.5 |
| Standard average incubation period for host eggs according to Chan (2012) | 12 |
n is the quantity of egg images taken for the analysis.
a
Significance of pairwise parameter comparisons (p < 0.05); the values without superscript index are insignificant.