There's two effects that the islands have on the size of the animals, reducing of size, or increasing of size. The reducing of size is known as island dwarfism, while the increase in size is known island gigantism.
The effect of the island environment effects different types of animals in different manner, and it also has to be taken in account the size of the island. In general, the small animals tend to increase their size on the islands, while the large animals tend to decrease in size. The reason for this is that the smaller animals, because of the isolation, usually lack predators or they are very few, but also have sufficient amounts of food, thus they grow in size. The larger animals though, decrease their size because there isn't enough food on the islands to support them, thus with the decrease in size they consume less. Also, since they usually lack predators, they do not have to be large in order to defend themselves.
As the number of organisms increase so does their tropic levels. As one organism eats the other energy is being transferred to that organism. The larger the food chain the lesser the organism' s would be because they would lose energy while trying to hunt and catch their prey and other activities. The food chain usually ends at the tertiary consumer or the fourth link because if it goes on like that there would be less energy hence these organisms would most likely starve and gradually die.
The Cross-Linkage Theory or also referred to as the glycosylation theory of aging was discovered or proposed by Johan Bjorksten in the 1940s. According to this theory, the aggregation of cross-linked proteins can damage cells and tissues this slowing down the bodily processes that eventually results to aging. In recent studies, cross-linking is associated with age-related changes in the studied proteins. Furthermore, this theory stresses out that the binding of glucose to proteins can cause various problems. Once the said binding occurs, the protein becomes impaired which leads to its performance inefficiency. Living a longer life would also mean increasing the possibility of oxygen-glucose meeting and protein. Some of the known cross-linking disorders include senile cataract and the appearance of tough, leathery, yellow skin.
