If you think the dating world is tough for a human, consider for a moment the Nopoli rock-climbing goby of Hawaii, which scales waterfalls up to 100 feet high in order to breed. To put this feat in perspective, it’s the equivalent of a man of average height scaling the 29,029 feet of Mount Everest!
The process leading to this incredible feat is, quite literally, jaw-dropping: the tiny one-inch goby propels itself up the waterfall rocks with two suckers – one, common to all gobies, on the belly, and a second, particular to one goby genus, that develops when the mouth migrates from the tip of its head to its chin over the course of 36 to 48 hours, before it embarks on its journey. The fish uses these dual suckers alternately to inch up the rocky substrate of waterfalls to the waters above where the goby mates and deposits eggs in streams. Upon hatching, these juvenile gobies are swept into the ocean where they develop for several months before they return to freshwater streams and pools upstream where they may live for several years. To mate, the gobies of this new generation must repeat the waterfall-climbing process themselves.