It's that time again to be afraid of entering the water: The Discovery Channel's 29th annual "Shark Week" is here. Whether you love them, fear them, or feel yourself inexplicably drawn to them, it's clear these formidable fish play an outsized role in the cultural consciousness. To celebrate their contributions to the zeitgeist, here are 10 things we've discovered about these animals in the past year.

As a group, sharks have been around for roughly 450 million years. But when it comes to individual lifespan, there's one species that appears to be the longest-lived vertebrates ever discovered. Unlike the tropical sharks many are familiar with, Greenland sharks live in the cold waters near the Arctic, giving them a slow metabolism rate that's "just above a rock," according to one shark researcher. This slow-motion living means they can survive for more than 400 years, but it also means that the sharks reproduce extremely slowly. This puts them at greater risk of extinction if many of them are killed off.

While we’re on the topic of reproduction, it turns out that some sharks do it in a very strange way. The mysterious "ghost sharks”—which get their name because they live deep underwater and are rarely seen—were found recently to have retractable sex organs on their heads. These organs have hooks that male ghost sharks use to grasp female ghost sharks during mating, which "does not seem to be a very pleasant experience for the females," according to biologist Brit Finucci. Thankfully, female ghost sharks appear also to be able to store sperm for years in special storage banks in their bodies, waiting until the right time to conceive.

Last August, the conservation group Ocearch made waves when one of its expeditions uncovered a rare great white shark nursery in the shallow waters just off the coast of New York. This was the first such nursery found in the northern Atlantic Ocean, and researchers believe the sharks spend the first 20 years of their life there. In general little is known about the migratory patterns of young sharks, making this "the most important significant discovery we’ve ever made,” according to Fischer.

Reef sharks are often depicted as the alpha predators of their habitats, akin to lions in the savannas of Africa. But that’s a myth popularized by humans, argue researchers studying fish in the Caribbean. "When we did our analysis, for each of the studies we looked at there was either no evidence of that kind of relationship or it was ambiguous or weak," ecologist Peter Mumby told Hakai Magazine. Instead, in many areas where sharks were fished, the population levels of herbivore fish didn't change substantially, meaning the sharks’ level of influence on their environments was lower than previously thought. Only a few of the largest shark species, such as tiger sharks, actually play the role of apex predator.

Larger than many of those sharks, however, was the newly described species Megalolamna paradoxodon, which grew to the size of a car when it roamed the world’s oceans. These giants lived 20 million years ago, and were identified in the past year from teeth found in the Pacific Ocean. Estimating from the teeth, researchers were able to extrapolate the extinct species to be about 12 feet in length, much larger than most humans, though smaller than the infamous great white shark, which can grow up to 16 feet long. The species may have been a close relative of other ancient sharks that grew to be five times that size.