It's almost certainly more eyes than legs on Earth.
Here's why: While humans have an equal number of eyes and legs (2 each), the animal kingdom is dominated by insects and other arthropods, many of which have more eyes than legs (e.g., spiders with 8 eyes and 8 legs) or many more legs than eyes (e.g., centipedes with many legs and two eyes). The sheer number of these creatures significantly outweighs the number of humans and other animals with an equal or greater number of legs than eyes.
Let's consider some examples:
- Humans: Approximately 8 billion humans 2 eyes = 16 billion eyes. Also, 8 billion humans 2 legs = 16 billion legs. So, humans contribute equally.
- Insects: There are estimated to be around 10 quintillion (10,000,000,000,000,000,000) individual insects. While the number of eyes varies (some have none, some have multiple ocelli in addition to compound eyes), even if most had fewer eyes than legs, the sheer volume would push the total number of eyes higher, especially considering many have compound eyes comprising thousands of individual lenses.
- Spiders: Spiders typically have eight eyes. Although there are far fewer spiders than insects, the ratio of eyes to legs is 1:1, so spiders contribute to the eye count.
- Other Animals: Many other animals like fish, birds, and mammals have two eyes and either two or four legs, making their contribution largely equal. Some animals, like snakes and worms, may have no legs, only further tipping the scales towards more eyes.
In Conclusion:
Due to the overwhelming population of insects and other arthropods, the total number of eyes on Earth significantly exceeds the total number of legs.
