Mekii eggs develop a tan, crust-like growth. Mekii eggs are very breathable and can get cold relatively quickly. Since Mekii mothers do not sit on their eggs to keep them warm, scientists in Ark have theorized that the crust-like growth is due to the process of evolution and adaptation since Mekii eggs have to maintain a higher than normal temperature in order to hatch.
Mekii hang out in the jungle of Ark, towards the center of the island near The Volcano. Like their eggs, they can get very cold quickly, hence their proximity to The Volcano (they like to live in niches of The Volcano). Mekii are the wisest creature known in Ark, but they are not without flaw; Mekii are extremely selfish. Thus, they prefer to be alone. It's best to let Mekii do what they want and it's advised not to hold Mekii unless you want your face rearranged.