Insects like spiders can sense predators with what organ of their body?

The air around an insect is in motion when it flies close by. Even sound vibrations cause the hairs to move due to air movement. Any movement is transmitted directly to the nerves because each hair is floating in a flexible membrane rather than being held tightly at the base. Each trichobothrium offers distinct information on the position and movement of the prey in respect to the spider due to differences in size and location. The nervous system quickly combines the data from the several trichobothria to create an accurate picture of where and when the spider must strike to snag its prey.