No, a fly does not have 7,000 eyes.
The Truth About Fly Eyes
Flies possess a surprisingly complex visual system, but it's far from having 7,000 individual eyes. Instead, they have a total of five eyes: three smaller, simpler eyes called ocelli located on the top of their heads, and two large compound eyes. These compound eyes are what we typically notice, and each one is made up of thousands of tiny individual units called ommatidia. Each ommatidia acts like a tiny lens, contributing to the fly's overall vision. While each compound eye contains thousands of ommatidia, these are not individual eyes.
- Ocelli (3): These three simple eyes help the fly detect light intensity and changes in light. They don't provide a detailed image like the compound eyes.
- Compound Eyes (2): These are the large, prominent eyes. Each compound eye is composed of numerous ommatidia. The number of ommatidia varies depending on the fly species but can reach into the thousands per eye, giving them a wide field of vision.
Therefore, the statement that a fly has 7000 eyes is incorrect. The number of ommatidia in a fly's compound eyes is in the thousands, not the overall number of eyes.
