Western diamondback rattlesnake
Crotalus atrox
— Where the name comes from
Crotalus comes from the Greek krótalon, the castanet, the percussion instrument: the rattle. Atrox is Latin, “fierce, frightful”. The name says exactly what the animal does and what it does to whoever hears it.
— Facts
- Group
- Reptiles · Reptilia
- Order
- Squamates
- Habitat
- Desert, arid grassland, thorn scrub
- Range
- The south-western United States and northern Mexico
- Size
- 120–150 cm
- Diet
- Carnivore — rodents, rabbits
- Lifespan
- about 20 years
— Characteristics
- 01
The loreal pits between eye and nostril are infrared organs.
- 02
The rattle is made of hollow keratin segments, one added at every moult.
- 03
The fangs fold back against the palate and swing forward for the strike.
— What sets it apart
The loreal pits register temperature differences of a few thousandths of a degree, and the snake’s brain fuses that thermal image with the visual one. This is not a metaphor: the two maps converge on the same optic tectum. The rattlesnake sees the warm shape of a mouse laid over the darkness of the desert, like native night vision.
