The Cuckoo primarily feeds on fruits, making it a frugivorous creature. However, there is an intriguing contradiction in its dietary habits when it comes to raising its young. Like all baby birds, Cuckoo chicks require a protein-rich diet to grow rapidly and stay healthy. This creates a dilemma as the adult Cuckoo’s fruit-based diet does not meet the needs of its offspring. This unique characteristic in the Cuckoo’s life cycle is the main factor contributing to its Brood Parasitic behavior.

The female Cuckoo quickly lays its eggs in the nests of other bird species such as Crows, Drongos, and even smaller birds like Bee Eaters. To accomplish this, the Cuckoo mother removes one or two eggs of the host parent and replaces them with her own. The Cuckoo’s egg has evolved to have a thicker and stronger shell, designed to withstand the process of being dropped into the host nest. Additionally, the Cuckoo’s egg hatches at a faster rate compared to other bird species.

Upon hatching, the Cuckoo chick instinctively produces continuous chirping, which compels the host parents to provide a larger quantity of urgent and protein-rich (non-vegetarian) food. The Cuckoo chicks may also eliminate the eggs or hatchlings of the host parent to ensure maximum attention and resources from their foster parents.

It is important to note that these behaviors are not driven by laziness, negativity, or evil intent. Similarly, it is incorrect to attribute love, generosity, positivity, or goodness to the host parent’s behavior. The actions observed in this brood parasitic relationship are simply a result of survival instincts and the principle of natural selection.

Furthermore, it has been brought to my attention by Jin Yi Tou that while some cuckoos may consume fruits, they are primarily insect eaters, with a specialization in feeding on caterpillars more than any other bird species.