Answer: King Cobra

Not only does the king cobra have the distinction of being the longest venomous snake in the world (they can reach lengths up to 19.2 feet/5.85 meters), but it also has a far more interesting distinction: it builds nests for its eggs.

The nests that king cobras create are not just to contain and shelter the eggs, but to actually incubate them. The cobra pushes together leaves and sticks to create what amounts to a compost pile. The decomposition of the organic material and the thermal mass of the mound keep the 7 to 43 eggs within at a temperature range of 56.3 to 99.3 degrees Fahrenheit (13.5 to 37.4 degrees Celsius). When the eggs finally hatch, the mother abandons her guard duty at the mound and quickly leaves the area to avoid eating her own young (as the king cobra’s diet is comprised almost entirely of smaller snakes).