WASHINGTON, DC.- The Smithsonians National Museum of Natural History
will open a new exhibition Nov. 9 revealing how millions of years ago, large-scale natural forces created the conditions for real-life sea monsters to thrive in the South Atlantic Ocean basin shortly after it formed. Sea Monsters Unearthed: Life in Angolas Ancient Seas will offer visitors the opportunity to dive into Cretaceous Angolas cool coastal waters, examine the fossils of striking marine reptiles that once lived there and learn about the forces that continue to mold life in the ocean and on land.
Over 134 million years ago, the South Atlantic Ocean basin did not yet exist. Africa and South America were one contiguous landmass on the verge of separating. As the two continents drifted apart, an entirely new marine environmentthe South Atlanticemerged in the vast space created between them. This newly formed ocean basin would soon be colonized by a dizzying array of ferocious predators and an abundance of other lifeforms seizing the opportunity presented by a new ocean habitat.
Because of our planets ever-shifting geology, Angolas coastal cliffs contain the fossil remains of marine creatures from the prehistoric South Atlantic, said Kirk Johnson, the Sant Director of the museum. We are honored by the generosity of the Angolan people for sharing a window into this part of the Earths unfolding story with our visitors.
For the first time, Angolan fossils of colossal Cretaceous marine reptiles will be on public display. Through Projecto PaleoAngolaa collaboration between Angolan, American, Portuguese and Dutch researchers focused on Angolas rich fossil historypaleontologists excavated and studied these fossils, which were then prepared for the exhibition by a team of scientists and students at Southern Methodist University (SMU) in Dallas. The exhibition was made possible by the Sant Ocean Hall Endowment Fund.
Fossils tell us about the life that once lived on Earth, and how the environments that came before us evolve over time, said Louis Jacobs, professor emeritus of paleontology at SMU and collaborating curator for the exhibition. Our planet has been running natural experiments on what shapes environments, and thereby life, for millions of years. If it werent for the fossil record, we wouldnt understand what drives the story of life on our planet.
The exhibition will immerse visitors in this Cretaceous environment with lively animations and vivid paleoart murals of life beneath the wavescourtesy of natural history artist Karen Carrthat bring to life 11 authentic fossils from Angolas ancient seas, full-size fossil reconstructions of a mosasaur and an ancient sea turtle, as well as 3-D scanned replicas of mosasaur skulls. Photomurals and video vignettes will transport visitors to field sites along Angolas modern rugged coast, where Projecto PaleoAngola scientists unearth the fossil remains from this lost world.
A Strange but Familiar Ocean
Sea Monsters Unearthed paints the picture of a flourishing ocean environment that in some ways will look strange to modern eyes, yet still bears striking similarities to todays marine ecosystems.
Peculiar plesiosaursmassive reptiles with long necks, stout bodies and four large flippersswam alongside 27-foot-long toothy marine lizards called mosasaurs and more familiar creatures like sea turtles. From surprising mosasaur stomach contents to the one of the oldest known sea turtles found in Africa, fossils and reconstructions of these species will offer visitors a fuller picture of their remarkable life histories and the ecosystems they were a part of.
The exhibition will also explore deeper similarities across the ecology and anatomy of ocean animals then and now. After the marine reptiles that dominated these waters went extinct 66 million years ago, modern marine mammals would not only later replace them as top predators in the worlds ocean, but also converge on many of the same body shapes and survival strategies.
The Forces That Shape Life, Then and Now
This unique period in Earths history reveals how key geologic and environmental forces contributed to the early establishment and evolution of life in the South Atlantic. As Africa and South America drifted apart and a new ocean basin formed, trade winds blowing along the new Angolan coastline created the conditions for upwelling, an ocean process that drives the circulation of nutrients from the deep ocean to its surface. These nutrients in turn jump-started the food web that attracted the ferocious marine reptile predators featured throughout the exhibition.
Just as tectonic forces helped create this Cretaceous marine environment, they also shaped the arid coastal cliffs where the fossils are found today. Starting 45,000 years ago, a geologic process called uplift caused Earths crust to bulge along Angolas coast, lifting part of the seafloor out of the waterand along with it, the layers upon layers of fossil-filled rocks where Projecto PaleoAngola scientists work.
Though humans do not operate on a tectonic scale, their actions also have major impacts on ocean life. Humans are now the oceans top predators, with one-fifth of the worlds population relying on food from upwelling-based ecosystems. Scientists caution that with such great pressure on modern upwelling-based fisheries, overfishing could change the future of life in the ocean by threatening fish populations, marine ecosystems and even human health.