The Ten Most Awe-Inspiring Ocean Moments of 2024

Amid a torrent of alarming headlines calling out rising sea temperatures, melting ice sheets and struggling coral reefs, new discoveries about our ocean sparked wonder. In 2024, scientists found the largest coral is bigger than a blue whale, how anglerfish became deep-sea denizens and that the ability for life to glow arose in the ocean half a billion years ago. Butterflies made a historic trans-Atlantic flight, an Antarctic penguin made a surprise appearance on a sandy beach, and a gray whale traveled thousands of miles from home.

In case you missed those huge saltwater stories and others, the National Museum of Natural History’s Ocean Portal team rounded up the ten most awe-inspiring ocean moments of the year and detailed them below.

Anglerfish developed strange sexual behavior to survive in the deep

Anglerfish look like creatures from another world, and their unique method for reproduction is equally peculiar. Males often permanently embed themselves in the bodies of their larger female counterparts, a relationship known as sexual parasitism. In some cases, the male may effectively become an attached sperm-producing organ. In a new study, scientists used DNA analysis and fossils to show that the sexual behavior evolved a long time ago to help them survive in the deep, open ocean. Anglerfish ancestors lived on the seafloor and maneuvered around using specialized stout fins, much like their close relatives the batfishes and frogfishes. Following the demise of the dinosaurs, Earth’s temperature spiked and put the ocean in a state of turmoil, and the early anglerfish began to explore more of the deep sea. Living in such a vast environment, the world’s largest ecosystem, means the chance of finding a mate is low. The evolution of sexual parasitism enabled a successful reproduction strategy that allowed the creatures to become the diverse, deep-sea swimming fish we know today.

Bioluminescence began in the sea

Fireflies blink in the night due to bioluminescence, but they’re not the only animals able to naturally produce light. Jellyfish, mushrooms, glowworms and others glow, too. This year Smithsonian scientists determined that the first instance of bioluminescence likely occurred in corals about 540 million years ago, close to 300 million years before the next known instance. Octocorals are soft-bodied corals—and most glow when bumped or disturbed, but we still don’t know why. In a first step to figure out this mystery, scientists traced the evolution of bioluminescence in the octocoral lineage using a combination of fossils and genetics. Since bioluminescence occurs in many present-day octocorals, scientists determined that their last common ancestor—an octocoral living 542 million years ago—produced light, too.

Sea turtle growth is affected by rain

Scientists have long known that, as with other reptiles, sea turtles’ egg development is influenced by the temperature of the nest. Warmer temperatures favor females and a quick development, while cooler temperatures allow for larger bodies and more males. Research published in August in BMC Ecology and Evolution now shows that rainfall also affects the developing baby turtle. Loggerhead turtles respond to heavier rainfall with smaller shells but greater weight, while green turtle hatchlings grow smaller shells without a change in body size. This is important because in the perilous world of a hatchling, shell and body size matter, as they can influence what types of predators are able to consume the young reptiles.

Animals explored the globe

Animals continue to surprise us as they travel thousands of miles from where they normally live. In November, beachgoers in Australia witnessed one such bizarre instance—a tuxedoed emperor penguin waddling toward the dunes. The penguin was over 2,000 miles from the icy shores of Antarctica where it normally lives and much farther north than where the species is often seen. Biologists interviewed about the animal thought the critter may have ventured to Australia in search of food.

Earlier in the year, a marine mammal wowed U.S. scientists. In March, a gray whale was spotted diving south of Nantucket in Massachusetts. Though once common in the Atlantic, gray whales were hunted and removed from that ocean about 300 years ago—and only five or so have been seen in the last 15 years there and in the Mediterranean. Scientists say this gray whale was likely the same one seen in Florida in December 2023, and its journey may have been aided by climate change. The Arctic’s Northwest Passage has recently been ice-free in the summer, which would allow the massive animals to move from the Pacific Ocean to the Atlantic Ocean.

A giant coral surpassed a record

A massive coral measuring longer than a blue whale was discovered off the coast of the Solomon Islands. The living structure, a Pavona clavus or shoulder blade coral, measures 112 feet wide, 105 feet long and 18 feet tall—and is thought to be more than 300 years old. Millions of genetically identical individual animals called polyps combine to form the largest coral to ever be discovered, and it can even be seen from space. The behemoth was accidentally found by scientists and filmmakers working for National Geographic’s Pristine Seas project.

Pesto made a big splash

Cute, fuzzy animals often go viral, so it’s no surprise that Pesto the penguin chick made waves across the internet. At about 52 pounds by nine months old, Pesto was the largest baby king penguin ever raised at the Sea Life Melbourne Aquarium in Australia. He weighed close to double the average adult penguin—thanks to a “hearty appetite” and good genes from his father, Blake. Pesto’s fame quickly spread after a public gender reveal, and he was viewed close to two billion times on social media. As the year closes, Pesto is beginning his awkward teen years and molting his endearing fluff in favor of adult feathers meant for swimming. Only time will tell his ultimate adult weight, but it will likely be close to the weight of other king penguins at 35 pounds.

Scientists discovered butterflies crossed the Atlantic

In 2013, a flock of battered painted lady butterflies were spotted in French Guiana in South America, halfway across the world from where they normally live in Europe and Africa. How they got there was a mystery—until this year. In a June study published in Nature Communications, scientists determined the find was the first documented case of insects travelling across the Atlantic Ocean. Using CSI-like forensics, the researchers sequenced the butterflies’ genomes and analyzed isotopes found in the insects’ wings to show they originated in either Africa or Europe. The butterflies also carried two types of pollen on their bodies, both from plant species found only in Africa. And favorable winds blew west across the Atlantic Ocean when the insects likely traveled. Together, all this evidence strongly indicated the painted lady butterflies traveled across the ocean—a Herculean feat that likely required flying and gliding for somewhere between five and eight days over more than 2,500 miles.

Another alien ocean may exist

Earth’s ocean isn’t the only ocean in this solar system. We’ve known of or suspected many others—including those of Jupiter’s moons Europa, Callisto and Ganymede and Saturn’s moons Enceladus and Titan. This February, another unlikely candidate joined the ranks. Researchers suggest Saturn’s “Death Star” moon Mimas may have a secret ocean hidden under miles of solid ice. An initial inspection of the cratered moon showed little indication that it could support so much liquid water. But after reanalyzing both Mima’s rotation and orbit around Saturn, scientists found slight shifts in both that together indicate the moon must have an ocean. The startling discovery offers hope there may be even more moons in our solar system with oceans—places that could potentially harbor life.

A photo of an orca wearing a salmon caused a stir

At the end of this year, news of an unusual fashion trend went viral across social media. An image of an orca donning a dead salmon on its head like a hat sparked speculation that an old 1980s fashion trend had returned. Decades ago, orcas in several pods off the West Coast began wearing dead salmon hats, but like all fads, it died off. Two recent sightings of orcas with salmon on their heads in Washington State brought widespread attention to the quirky behaviors of killer whales, but experts caution that it’s unlikely to be a true fashion revival. Since the initial two reports there have not been any more sightings. Whales, like humans, display personality traits, and while we may never know why these particular orcas recently wore the dead salmon, the story was certainly amusing.

A deep-sea expedition uncovered new species

This April, a team of scientists announced they found a vibrant community of sponges, corals, lobsters, squids and myriad other creatures while diving off the coast of Chile. A recent Schmidt Ocean Institute expedition to the underwater mountains of the Salas y Gómez Ridge identified 160 species not previously known to live in the region, with 50 of them being completely new to science. During their explorations, the team set a record—documenting the deepest-known photosynthesis-dependent creature in the oceans, a so-called wrinkle coral. The research cruise was just one of many in which the Schmidt Ocean Institute made new discoveries in the Pacific—in January it found 100 suspected new species, and in August it announced another 20 new species. The team’s work continues to show the great diversity of shapes and sizes of creatures of the deep.