Final answer:
A Type II survivorship curve shows a consistent mortality rate across all ages, common in bird populations, unlike Type I or Type III curves, which show increased mortality in older or younger ages respectively.
Step-by-step explanation:
A Type II survivorship curve is characterized by a relatively constant rate of mortality throughout an organism's life. This means that individuals in the population are equally likely to die at any age. Birds often exhibit this type of survivorship curve, where the likelihood of death does not depend notably on age, contrasting with the patterns seen in Type I and Type III curves. In a Type I curve, seen in humans and many mammals, mortality rates are low for the young and middle-aged and increase for older age groups. On the other hand, a Type III curve, typical of trees and some invertebrates, shows a very high mortality rate for juveniles, but a much lower rate for those that survive to older ages.