They have colour-changing skin three hearts and bluish-green blood. Their tentacles pull other creatures for eating. No they are not aliens from another planet. They are cuttlefish and they are found in our very own oceans.
Cuttlefish are considered the most intelligent invertebrates. This brainy group includes the octopus squid and chambered nautilus. They are so smart that scientists have taught them to do new things. And they remember what they have learned.