Top Discoveries at the National Museum of Natural History in 2024 | Smithsonian Voices

In 2024, researchers at the National Museum of Natural History contributed to hundreds of scientific publications. These papers named new species, described geological processes and provided insights into the interactions between early human species.

Here are the top discoveries by NMNH scientists that garnered the most headlines in 2024.

Earth’s global temperature has drastically changed over the past 485 million years

During the Phanerozoic Eon, a vast swath of geological time that began around 540 million years ago, life diversified, populated land and endured multiple mass extinctions. All of these evolutionary milestones happened amid a backdrop of Earth’s constantly changing climate. However, the fragmented fossil record has made it difficult to gauge just how much the planet’s temperature has fluctuated across the eon.

Museum paleobiologists Scott Wing and Brian Huber recently worked with an international team of researchers to create a detailed curve of Earth’s global surface temperature over the past 485 million years. Their findings, published in the journal Science, reveal that global mean surface temperatures have varied more than previously thought and are strongly correlated to the amount of carbon dioxide in the atmosphere.

Emily Judd, a former postdoctoral researcher at the museum, helped lead the effort, which utilized an approach called data assimilation to combine data from the geologic record and climate models. “This method was originally developed for weather forecasting [but] instead of using it to forecast future weather, here we’re using it to hindcast ancient climates,” Judd said.

The climate curve revealed that Earth’s current global temperature is cooler than during much of the Phanerozoic. But greenhouse gas emissions are currently warming Earth’s temperature much faster than any other time during the Phanerozoic. This rapid rate of warming puts species and ecosystems around the world at risk.

Bioluminescence in ancient corals evolved 540 million years ago

A variety of creatures, including glow worms, squids and anglerfish, utilize chemical reactions in their bodies to produce light. Known as bioluminescence, this behavior has evolved nearly 100 different times, making it difficult to discern when exactly animals first began to glow.

A team of researchers, including Andrea Quattrini, the museum’s curator of corals, and Danielle DeLeo, a museum research associate and former postdoc, recently examined the evolution of octocorals. This ancient group of animals includes soft corals and sea fans, many of which produce bioluminescence when disturbed.

The team compared octocoral fossils and genetics to create an evolutionary tree for the group. Their analysis, published in the Proceedings of the Royal Society B in April, revealed that octocorals began producing bioluminescence at least 540 million years ago. This is nearly 300 million years older than the previous estimate for the dawn of bioluminescence.

Fossilized footprints reveal that early human relatives crossed paths

1.5 million years ago, on the outskirts of an ancient lake in what is now northern Kenya, human relatives called hominids left their footprints. These tracks were not one size fits all—one set of prints was left by a flat foot with a wide, big toe, while other sets were left by a foot with a higher arch.

These fossilized footprints were recently analyzed by an international team of researchers that included Kay Behrensmeyer, the museum’s curator of vertebrate paleontology. Due to the differing anatomy of the footprints, the researchers concluded that the prints belonged to two distinct species of ancient human relatives. The flat-footed prints were made by an extinct hominid group called Paranthropus boisei, while the high-arched prints were left by Homo erectus, a close relative to modern humans. These findings were published in the journal Science in November, providing the first evidence of two different human relatives coexisting in the same area.

To safeguard biodiversity, researchers are considering the moon as a potential location for a biorepository. Scientists are exploring cryopreservation methods for samples from various species, such as starry gobies, to prepare for potential lunar storage. The project is inspired by the Svalbard Global Seed Vault in Norway, which is under threat from climate change.

The practice of ant agriculture began after an asteroid impact, with ants and fungi evolving together over millions of years. Leafcutter ants, in particular, have mastered advanced agricultural practices after millions of years of coevolution with fungi. This research was published in the journal Science in October.

An international team of researchers analyzed DNA from over 9,500 species of flowering plants to create a detailed tree of life for angiosperms. The study, published in Nature in April, provides insights into the evolution and relationships of various botanical groups, including extinct species preserved in museum herbariums.

A newly described species of proto-amphibian, Kermitops gratus, was named after the Muppet character Kermit the Frog. The fossil skull, unearthed in Texas, displays characteristics of both older tetrapod groups and younger amphibians. This discovery was published in the Zoological Journal of the Linnean Society in March.

Fossil grape seeds from the Western Hemisphere represent the earliest known species of grape relative, Lithouva susmanii. These seeds indicate that fruit thrived after a mass extinction event, shedding light on the resilience of plant species over time. The original fossil, CT scan, and artist reconstruction of both sides of the seed are shown in the images above. The fossil was discovered by Fabiany Herrera and the reconstruction was done by Pollyanna von Knorring.

When an asteroid collided with Earth 66 million years ago, it led to a mass extinction event that wiped out nearly half of all plant species. However, this event also created space for new flowering plants to thrive, including grape-producing plants.

A team of scientists, led by USDA botanist Gregory Stull, uncovered fossilized grape seeds in Colombia, Panama, and Peru. They described nine ancient grape species, four of which are newly discovered. One of the new species, Ampelocissus wenae, was named after botanist Jun Wen.

In September 2023, NASA’s OSIRIS-REx dropped off a capsule containing rock and dust samples from the asteroid Bennu. These samples, weighing slightly more than four ounces, may provide insights into the origins of water and life on Earth.

An international team of researchers, including Tim McCoy, published an initial description of the Bennu samples in June. This lays the groundwork for future analyses of the asteroid’s mineralogical and chemical properties.

Research zoologist Gary Graves collaborated with a team of scientists to compare the genomes of 363 bird species. Their work, published in the journal Nature in April, provided valuable insights into avian evolution.