Food shortage in a population can lead to intra-specific competition. When there is not enough food to go around, individuals within the same population will have to compete with each other for limited resources. This can lead to a decrease in overall fitness, as weaker individuals may not be able to obtain enough food to survive and reproduce. It may also result in changes in behavior, such as increased aggression or territoriality. Ultimately, a population that experiences prolonged food shortage may suffer from reduced growth rates, increased mortality, and decreased reproductive success.