Table 1.
Reproductive senescence in toothed whales inferred from physiological analysis.
| Common name | Species name | Age vs Corpora relationship | Relative rate of reproductive senescence | Phys-PrR stable population [shrinking population – growing population] | Conclusion |
|---|---|---|---|---|---|
| Beluga whale | Delphinapterus leucas | Polynomial | 1.69 | 0.27* [0.19*–0.33*] | Reproductive senescence and post-reproductive lifespans |
| Narwhal | Monodon monoceros | Polynomial | 1.48 | 0.24* [0.19*–0.29*] | Reproductive senescence and post-reproductive lifespans |
| Short-finned pilot whale | Globicephala macrorhynchus | Polynomial | 1.38 | 0.15* [0.08*–0.22*] | Reproductive senescence and post-reproductive lifespans |
| Baird’s beaked whale | Berardius bairdii | Polynomial | 0.87 | 0.01 [0.00–0.02] | Reproductive senescence |
| False killer whale | Pseudorca crassidens | Polynomial | 0.77 | 0.03 [0.02–0.08] | Reproductive senescence |
| Long-finned pilot whale | Globicephala melas | Polynomial | 0.62 | 0.01 [0.00–0.02] | Reproductive senescence |
| Northern right-whale dolphin | Lissodelphis borealis | Polynomial | 1.14 (0.75) | 0.03 [0.02–0.05] | Reproductive senescence |
| Pantropical spotted dolphin | Stenella attenuata | Polynomial | 0.84 | 0.02 [0.01–0.03] | Reproductive senescence |
| Sperm whale | Physeter macrocephalus | Polynomial | 0.64 | 0.00 [0.00–0.01] | Reproductive senescence |
| Spinner dolphin | Stenella longirostris | Polynomial | 0.89 | 0.01 [0.01–0.02] | Reproductive senescence |
| Common bottlenose dolphin | Tursiops truncatus | 1. Linear 2. Linear 3. Linear |
n/a | n/a | No reproductive senescence |
| Melon-headed whale | Peponocephala electra | Linear | n/a | n/a | No reproductive senescence |
| Striped dolphin | Stenella coeruleoalba | Linear | n/a | n/a | No reproductive senescence |
| Atlantic white-sided dolphin | Lagenorhynchus acutus | No correlation | n/a | n/a | Corpora are not a good measure of ovarian activity. |
| Harbour porpoise | Phocoena phocoena | No correlation | n/a | n/a | Corpora are not a good measure of ovarian activity. |
| Short-beaked common dolphin | Delphinus delphis | No correlation | n/a | n/a | Corpora are not a good measure of ovarian activity. |
The relative rate of reproductive senescence is calculated relative to somatic senescence using normalised data. A rate of exactly 1 would mean that ovarian activity is declining linearly with age. A rate of greater than 1 implies that ovarian activity is declining more slowly than somatic senescence. Rate in parentheses is the rate without a single outlying older individual. Phys-PrR (physiological post-reproductive representation) is the proportion of female years being lived by post-reproductive females in the population (those marked with an * are significantly different from 0).