Above, the 20-ft-tall (6m), palm-like tree in full bloom next to a bank along Mérida's Paseo de Montejo is a native Yucatec plant found in the Peninsula's more arid, scrubby parts. Northerners sometimes think it must be some kind of yucca or maybe a palm, but it's unrelated to those plant groups. It's the Mexican Ponytail, also known as the Ponytail Palm, Elephant-Foot Tree, and by many other names. It's Beaucarnea pliabilis.
Probably you are more accustomed to seeing Mexican Ponytail in pots where sometimes they produce very large, spherical, water-storing bulges at their trunk bases. Often you see them in hotel lobbies and the like. They're planted in the tropics worldwide because they are such unusual, handsome plants.