Off Monterrey, California (western United States), scientists have discovered the largest octopus nursery in the world. Three kilometers down, more than a thousand female octopuses were nestled on rocks in the process of cover. Their discovery was possible thanks to the use of a remote-controlled underwater vehicle. One of the hypotheses put forward demonstrating the presence of many octopuses in this region of the globe would be the quality of the rocks. But scientists are not ruling out any tracks for the time being. Proof that deep waters still hold many mysteries...