Table 1 Published studies testing for an interaction between inbreeding depression and environmental variation in free-living populations
From: Inbreeding depression by environment interactions in a free-living mammal population
Species | Method for estimating inbreeding | Amount of inbreeding in pop | Whose inbreeding is being studied? | Trait | Sample size | Inbreeding depression main effect detected? | Environmental variable(s) tested | Environmental variable(s) that interacted with ID | Effect on inbreeding depression | Reference |
|---|---|---|---|---|---|---|---|---|---|---|
Soay sheep, Ovis aries | Microsatellite heterozygosity | 8/899=6.1% of individuals with all 4 grandparents known have Fped ⩾0.125. | Individual adults | Fecal egg count | 398 | Y | Year | Year | ID more severe in high density years | |
Cactus finch, Geospiza scandens | Social pedigree F | 3.3% Of individuals with all 4 grandparents known have Fped ⩾0.25 | Individual | Survival from banding to age 1 year | 120 | Y | Annual rainfalla, density of G. scandens, density of G. fortis and all interactions between | Annual rainfall | ID only apparent when rainfall low | |
Individual | Adult annual survival | Y | Annual rainfall, density of G. scandens, density of G. fortis and all interactions between | Annual rainfall × density of G. scandens | ID more severe when rainfall low and G. scandens density high | |||||
Individual | Adult annual probability of breeding | Y | Annual rainfall, density of G. scandens, density of G. fortis and all interactions between | None | NA | |||||
Medium ground finch, Geospiza Fortis | Social pedigree F | 0.8% Of individuals with all 4 grandparents known have Fped ⩾⩾0.25. | Individual | Survival from banding to age 1 year | 364 | N | Annual rainfall, density of G. fortis, density of G. scandens and all 2-way interactions between | None | NA | |
Individual | Adult annual survival | N | Annual rainfall, density of G. fortis, density of G. scandens and all interactions between | None | NA | |||||
Individual | Adult annual probability of breeding | Y | Annual rainfall, density of G. fortis, density of G. scandens and all interactions between | None | NA | |||||
Collared flycatcher, Ficedula albicollis | Social pedigree F | 16/2107=0.8% clutches with sufficient pedigree to detect Fped=0.125 had Fped ⩾0.25. | Clutch | Clutch size | 2088 | N | Average body condition in year of birth | None | NA | |
Clutch | Hatching success | 2066 | Y | Average body condition in year of birth | None | NA | ||||
Clutch | Fledging success | 2065 | N | Average body condition in year of birth | None | NA | ||||
Clutch | Fledgling tarsus length | 1971 | Y | Average body condition in year of birth | None | NA | ||||
Clutch | Fledgling body condition | 1966 | N | Average body condition in year of birth | None | NA | ||||
Clutch | Juvenile survival | 1760 | Y | Average body condition in year of birth | None | NA | ||||
Clutch | Recruitment per nest | 1764 | Y | Average body condition in year of birth | None | NA | ||||
Seychelles warbler, Acrocephalus sechellensis | Microsatellite heterozygosity | 5% Of 119 offspring estimated to be due to matings between first-order relatives | Female parent | Offspring survival | 119 | N | Breeding season | Breeding season | In a low-survival breeding season, offspring survival was correlated with maternal heterozygosity, but not in other seasons. | |
Song sparrow, Melospiza melodia | Social pedigree F | <10% Of birds in male mating success analysis had F ⩾0.125 | Adult male | Male mating success | 680 Obs on 262 males | Y | Number of males, males per female | None | NA | |
Male social parent | Offspring survival from 12 to 24 days | 650 Obs on 179 males | Y | Rainfall in 2-day, 3-day and 4-day rainiest intervalb | None | NA | ||||
Female parent | Laying date | 371 Obs on 166 females | Y | Average daily temperature measured across six different pre-laying time intervals | None (second best model showed an interaction with temperature) | NA (second best model suggests reduced difference between inbred and outbred females under cool temperatures) | ||||
Female parent | Hatching success | 640 Obs on 155 females | Y | Average daily rainfall across four time intervals during incubation | Average daily rainfall in all the intervals studied | Increased ID in rainy conditions. | ||||
Great tit Parus major | Social pedigree F | 58/4523=1.3% of broods with both parents and one grandparent known have Fped ⩾0.125 | Breeding events (=clutches) | Number of offspring recruited | Around 4500 clutches | Y | Population density, local oak density, female age, male age, local population density, distance from forest edge, caterpillar lag, yearly fledging mass, winter beech mast, yearly recruitment quality (all grouped into above and below average) | Yearly fledging mass | Increased ID in years of low fledging mass | |
Stewart island robin, Petroica australis rakiura | Social pedigree F (with some genetic support) | 29/182=15.9% of broods have Fped ⩾0.125. All four grandparents known for 96% of broods. | Brood, female parent, male parent | Hatching success | 182 Broods | N | Min temperature during nesting period, rainfall during nesting period,c habitat type. | None | NA | |
Brood, female parent, male parent | Fledging success | N | Min temperature during nesting period, rainfall during nesting period, habitat type. | None | NA | |||||
Brood, female parent, male parent | Recruitment success | N | Min temperature during nesting period, rainfall during nesting period, habitat typez | None | NA | |||||
Red deer, Cervus elaphus | Genetic pedigree F | 36/1848=2% Of individuals with both parents and at least one grandparent known inbred at Fped ⩾0.125 | Calf and mother | Birth date | 2515 Calves from 602 mothers | Offspring F: N, maternal F: N | Year of birth | None | NA | |
Birth weight | 1664 Calves from 487 mothers | Offspring F: Y, maternal F: N | Year of birth | None | NA | |||||
First year survival | 1593 Calves from 463 mothers | Offspring F: Y, maternal F: N | Year of birth | None | NA | |||||
First winter survival | 1400 Calves from 443 mothers | Offspring F: Y, maternal F: N | Year of birth | None | NA | |||||
Meerkats Suricata suricatta | Genetic pedigree F | 71/1583=4.4% of pups had Fped ⩾0.125. All four grandparents known for 97% of pups. | Pup | Emergence mass | 422 | Y | Number of lactators Number of helpers | Number of lactators | ⩽4 Lactators increased emergence mass, but ⩾5 lactators depressed that of inbred pups | |
Hindfoot length | 219 | Y | Number of lactators Number of helpers Season Rainfall | None | NA | |||||
Growth until independence | 523 | Y | Number of lactators Number of helpers Rainfall | Number of lactators | More lactators were associated with slower growth of inbreds. |
