“Morocco has revealed itself as a fossil treasure trove for ancient life." -Dr. Peter von Roy of Ghent University, Belgium (co-describer of Aegirocassis and Calvapilosa).
Though North Africa is generally seen as synonymous with the Sahara Desert, this huge, harsh landscape is a geologically-recent feature, not originating until around 7 million years ago. Prior to this development, North Africa was a lush, wet, ecologically-rich region -- especially modern Morocco, roughly 500, 100, and 50 million years ago.
In the past few years especially, paleontologists have unveiled amazing new creatures from Morocco's distant past -- from the largest meat-eating dinosaurs and the first ancestors of elephants to bizarre sea turtles and bewildering ancient invertebrates. Few of these animals are known from even half-complete specimens, yet their fossils are complete enough to tell us what ecological roles they played and how they relate to animals beyond their time and space.
Ironically, the brightest stars of pre-Sahara Morocco all lived in or around the water.
Drâa-Tafilalet to Laâyoune-Sakia El Hamra, 480-466 million BCE ("before the common era"; same dating as BC)
The Ordovician Period began around 485 million BCE and ended around 444 million BCE -- over two hundred million years before the first dinosaur and about seventy million years before the first vertebrates colonized the land. At the time, North Africa was underwater and located close to the South Pole. In 2015 and 2017, paleontologists unveiled two striking Ordovician invertebrates from the Fezouata Formation of southeastern Morocco:
The first and larger of the two is Aegirocassis ("Aegir's helmet", after a sea giant from Norse mythology). Debuting in 2015, this creature belonged to the anomalocaridids, an extinct group of arthropods distantly related to modern crustaceans, insects, and arachnids. At nearly seven feet long, Aegirocassis was the largest creature on Earth during the Early Ordovician and one of the biggest arthropods of all time. It was a filter-feeder like modern baleen whales, sifting plankton into its mouth with its brush-like appendages and propelling itself through the water with forty-four triangular flaps along its segment body. As if its appearance wasn't surprising enough, Aegirocassis' remains were preserved in three dimensions, unlike the flattened fossils of many other ancient invertebrates.
The second new oddball was Calvapilosa ("hairy scalp"), an early mollusk announced in February of 2017. Like most living mollusks (including limpets, snails, and octopi), this invertebrate had a line of hard, tooth-like structures called a radula, used to scrape food into its mouth. Similar animals are known from the Cambrian Period (the one that preceded the Ordovician), but until the discovery of Calvapilosa, paleontologists believed these bizarre creatures had gone extinct by the Ordovician Period and weren't sure how they related to modern animals.
Dr. Jakob Vinther, one of the scientists who studied and named Calvapilosa, believes that it was an ancestor to modern chitons -- flat, eight-shelled mollusks that still feed on algae on the seafloor.
“If we trace back the evolution of chitons, we can see that the number of their shells has increased with time,” Vinther says. “It is therefore likely that the ancestor to all mollusks was single-shelled and covered in bristle-like spines, not dissimilar to [Calvapilosa].”
Too Many Meat-Eaters?
Oriental and Drâa-Tafilalet, 112-93 million BCE
By the middle of the Cretaceous Period (145 to 66 million BCE), the seven modern continents were approaching their present positions. Africa was an island continent which Madagascar and India would break from together around 88 million BCE. Morocco's Kem Kem Beds date the early to mid-Cretaceous and like the Fezouata Formation, the area has two immediate stand-out animals -- both of which were meat-eating dinosaurs bigger than T. rex.
Though first discovered in Egypt and still not known from a complete skeleton, the best Spinosaurus ("spine lizard") fossils uncovered so far hail from Morocco. In life, this predator measured around fifty feet long and probably used its crocodile-like jaws and hooked claws to catch and tear apart large fish.
In 2014, paleontologist Paul Sereno and his colleagues posited that Spinosaurus was a quadrupedal, semi-aquatic animal, based in part on its long, flat feet, which resemble those of wadding birds; its unusually dense bones, which may have provided ballast just as those of hippos and penguins do; and its front-heavy design, which would have made walking on land a trial for such a huge animal. While not all paleontologists agree with Sereno about this proposed lifestyle, there is a consensus that Spinosaurus' sail was probably for display -- perhaps to intimidate rivals or to indicate its age or sex.
The second most-famous dinosaur from the Kem Kem Beds is Carcharodontosaurus ("razor-toothed lizard"). A distant, larger relative of the earlier Allosaurus, this predator had a skull over five feet long and reached up to forty-five feet long -- shorter than the largest Spinosaurus but a few feet longer than the biggest mounted T. rex skeleton. Unlike T. rex, Carcharodontosaurus had longer arms ending in three fingers but narrow, weaker teeth and jaws better for slicing through skin and flesh than delivering bone-crushing bites.
Other predators are known from the Kem Kem Beds as well, including medium-sized carnivorous dinosaurs, crocodiles, giant coelacanths and saw-toothed sharks, and Alanqa, a pterosaur with a twenty-foot wingspan. Sereno and his colleagues believe that all these predators were able to thrive together by specializing in different kinds of prey and competing with each other as little as possible: Spinosaurus fed on the large fish, which in turn ate smaller fish. The crocodiles would have pursued fish too but also would have hunted turtles and any small creatures that came too close to the water. Meanwhile, on land, Carcharodontosaurus attacked and ate the large plant-eating dinosaurs, and the other meat-eating dinosaurs would have focused on smaller dinosaurs and carrion. Alanqa may have fed on a bit of everything, hunting small fish, turtles, and small dinosaurs but also feeding on leftover Spinosaurus and Carcharodontosaurus meals.
One question not fully answered by the Kem Kem Beds so far is who the local herbivores were. As of writing, the one plant-eating dinosaur known from these sediments is the long-necked, long-tailed Rebbachisaurus, a distant relative of Apatosaurus and Diplodocus.
Turtles with Blowholes and Elephants without Trunks
Rabat-Salé-Kénitra and Béni Mellal-Khénifra, 70-55 million BCE
Lying about sixty miles southeast of Casablanca, the Ouled Abdoun Basin is Morocco's largest phosphate deposit. This basin also preserves fossils dating from both before and after the extinction of the dinosaurs around 66 million BCE.
Before the extinction, central Morocco was underwater and inhabited by marine reptiles like plesiosaurs, mosasaurs, and crocodiles. While the local plesiosaur Zarafasaura had an unusually short skull and is known from a near-complete skeleton, the real standouts from these deposits are two bizarre, recently-known sea turtles known only from their skulls: Ocepechelon ("the Office of Chérifien Phosphates' turtle") was named and announced in 2013 and had a long, triangular snout used for suction-feeding, trapping small fish and invertebrates in its tiny mouth. Debuting the next year, Alienochelys ("alien turtle") had a short, broad, almost duck-like beak and probably fed on crustaceans on the seafloor. Both of these turtles were gigantic cousins of the living leatherback sea turtle and both of them had nostrils located between the eyes like modern baleen whales.
After the extinction of the dinosaurs, the future Ouled Abdoun Basin dried out and hosted crocodiles, freshwater turtles, and the three earliest-known proboscideans -- the family of mammals that comprises elephants and their extinct relatives. From oldest to youngest and smallest to largest, these elephant ancestors are Eritherium ("early beast"), Phosphatherium ("phosphate beast"), and Daouitherium ("beast from Sidi Daoui") -- ranging from 60 to 55 million years old and from rabbit- to pig-sized animals. All three were tuskless, trunkless animals that probably led hippo-like lifestyles, living and feeding near or in freshwater. Wear marks on the teeth of Phosphatherium suggest that these herbivores were already tackling tough plants, an adaptation critical to the success of later, larger proboscideans.
Proboscideans wouldn't be fully-terrestrial animals until around 35 million BCE and wouldn't leave Africa for another fifteen million years.
Other Moroccan fossil sites
- Trilobites from the Devonian Period (419-359 million BCE) are common in Morocco, especially the Ghtira Limestone in Rabat-Salé-Kenitra, the Timrhanrhart Formation in Souss-Massa, and the Megrane Shale in Oriental.
- The youngest fossils attributed to Diplocaulus, a boomerang-headed amphibian from the Permian Period (299-252 million BCE), come from the Ikakern Formation in Marrakesh-Safi.
- The Argana Basin in Marrakesh-Safi preserves the remains of large, non-dinosaur reptiless from the mid-Triassic Period (around 235-220 million BCE), as well as footprints left by proto-dinosaurs.
- Tazoudasaurus and Atlasaurus are among the oldest large sauropods known from Africa, discovered in the Toundoute Group in Drâa-Tafilalet and the Guettioua Formation in Marrakesh-Safi, respectively. Tazoudasaurus was about thirty feet long and lived during the Early Jurassic (around 180 million BCE), while Atlasaurus was around fifty feet long and lived later during the same period (around 165 million BCE).
- Fossils from the Ksar Metlili Formation in Béni Mellal-Khénifra date to the beginning of the Cretaceous Period (around 145 million BCE) and include the burrowing amphibian Rubricacaecilia and the carnivorous mammal Ichthyoconodon.
- Thililua, a long-snouted, twenty-foot-long plesiosaur that lived around 90 million BCE, hails from the Akrabou Formation in Drâa-Tafilalet.
- Bones and tools belonging to Homo heidelbergensis -- the last common ancestor of Neanderthals and modern humans -- have been found in the Grotte à Hominidés near Casablanca. One bone, dating to about 500 thousand BCE, has bite marks on it that were probably left by a hyena.
Anderson, Natali. "Ocepechelon: Giant Prehistoric Sea Turtle from Morocco." Sci-News.com, 22 Jul 2013.
Geggel, Lauren. "Photos: Ancient Sea Monster Was One of Largest Arthropods." LiveScience, 11 March 2015.
Gheerbrant, Emmanuel. "Paleocene emergence of elephant relatives and the rapid radiation of African ungulates." Proceedings of the National Academy of Sciences, Vol. 106, Issue 26, p. 10717–10721, 11 May 2009.
Gheerbrant, Emmanuel et al. "A new large mammal from the Ypresian of Morocco: Evidence of surprising new diversity of early proboscideans." Acta Palaeontologica Polonica, Vol. 47, Issue 3, p. 493–506, 2002.
de Lazaro, Enrico. "Tooth-Marks on 500,000-Year-Old Bone Indicate Hominin Hunting/Scavenging by Large Carnivores." Sci-News.com, 29 April 2016.
Mueller, Tom. "Mister Big." National Geographic, Oct 2014. (Issue about the new Spinosaurus)
"Ordovician Fossil Sheds New Light on Early Evolution of Mollusks." Sci-News.com, Feb 6 2017.
Perkins, Sid. "Newly discovered sea creature was once the largest animal on Earth." Science, 11 Mar 2015.
Prostak, Sergio. "Paleontologists Describe First Near-Complete Specimen of Moroccan Plesiosaur Zarafasaura oceanis." Sci-News.com, 30 May 2013.
"Sahara Desert Formed 7 Million Years Ago, New Study Suggests." Sci-News.com, 20 Sep 2014.
"Spinosaurus aegyptiacus: Paleontologists Unveil First Semiaquatic Dinosaur." Sci-News.com, 12 Sep 2014.
Switek, Brian. "The New Spinosaurus." National Geographic (Phenomena), 11 Sep 2014.
ed. Brett-Surman, M.K., Thomas R. Holtz, Jr, and James O. Farlow. The Complete Dinosaur: Second Edition. Indiana University Press, Indianapolis, IN, 2012.
ed. Burnie, David and Don E. Wilson. Smithsonian Animal: The Definitive Visual Guide. Dorling Kindersley, New York, NY, 2011.
Palmer, Douglas et al. Prehistoric Life: The Definitive History of Life on Earth. Dorling Kindersley, New York, NY, 2009.
Paul, Gregory S. The Princeton Field Guide to Dinosaurs. Princeton University Press, Princeton, NJ, 2010.
Prothero, Donald R. The Princeton Field Guide to Prehistoric Mammals. Princeton University Press, Princeton, NJ, 2016.
Steyer, Sébastien. Earth Before the Dinosaurs. Indiana University Press, Bloomington, IN, 2012.
Switek, Brian. Written in Stone: Evolution, the Fossil Record, and Our Place in Nature. Bellevue Literary Press, New York, NY, 2010.
"Quick Bite: Ocepechelon the Whale Turtle." Past Time, 21 Jul 2013.
"Quick Bite: The Alien Turtle and Ancient Color." Past Time, 21 Jan 2014.