| cattle | butterfat percentage | 60% |
| milk yield | 30% | |
| pigs | body length | 50% |
| weight at 180 days | 30% | |
| litter size | 15% | |
| poultry | egg weight | 60% |
| annual egg production | 30% | |
| body weight | 20% | |
| viability | 10% | |
| fruit fly | abdominal bristle number | 50% |
| body size | 40% | |
| ovary size | 30% | |
| egg production | 20% | |
Falconer, D. S. (1960) Introduction to quantitative genetics. R Mac Lehose and Company, Glasgow.