Many animals have superior night vision due to specific adaptations in their visual systems. These nocturnal adaptations include:
- Larger eyes relative to body size
- More rod cells (responsible for low-light vision)
- A reflective layer called the tapetum lucidum
- Wider pupils that let in more light
For example, cats have a tapetum lucidum that reflects light back through their retina, giving them a second chance to capture light and resulting in their characteristic eye shine. They can see in light levels six times dimmer than what humans need. Similarly, owls have extremely large eyes and densely packed rod cells, allowing them to hunt effectively in near-darkness. These adaptations evolved to help animals survive in their specific ecological niches.