Final answer:
Growth traits like weaning weight and yearling weight are influenced by genetics and environment, and their heritability can vary. They can sometimes be inherited together, and understanding their heritability is important for selective breeding and managing populations.
Step-by-step explanation:
Growth traits such as weaning weight (weaning wt) and yearling weight (yearling wt) are examples of quantitative traits that can be measured and are influenced by both genetics and environment. The heritability of a trait refers to the fraction of phenotype variation that can be attributed to genetic differences among individuals in a population. These traits can show varying degrees of heritability depending on the genetic basis and environmental factors affecting the population.
Mendelian genetics illustrate that not all traits are inherited separately; some can be inherited together. This is evident when we observe offspring that appear to be a 'blend' of their parents' traits especially in characteristics showing continuous variation such as height or weight. It is crucial to understand that while heritability can inform us about the potential for a trait to respond to selection in a population over time, it does not predict the outcome for an individual organism.
Studies, such as the one by Grotkopp and Rejmánek (2007), indicate that certain traits may be associated with growth patterns in plants, and similar principles apply to animal growth traits. The heritability in growth traits can have implications for areas such as agriculture or conservation, where understanding the genetic and environmental contributions to these traits can be vital for selective breeding or managing populations.