Well, I hope you are not afraid of water and spiders at the same time, because, once upon a time during the Cambrian period, a giant creature with multiple legs resembling a spider used to rule the seas five hundred million years ago. Be thankful that you did not have to worry about giant spiders when you go to the beach.
Sadly the five hundred million year old sea spiders had such soft bodies, as did most organisms during the Cambrian period, that many of them failed to leave an impression as a fossil, despite being surrounded by sediments necessary to encase most animals of today. However, the researchers exploration was not entirely without academic benefit as the group spotted many tracks along the ground that suggested the presence of a multi-legged worm, similar to the multiple legged worm that bullied all other sea creatures for millions of years.
What do you think recreational beach going would be like today if some of these terrifying creatures had survived?