Dr. Iyad Zalmout

Carbonate rocks, shales, and marl of the Dammam Formation preserve a shallow marine ecosystem from when the eastern Arabian Peninsula lay beneath the Tethys Sea—46 million years before today's Khurais desert. In a deep-dive interview with Arab News, Iyad Zalmout—technical adviser at the SGS Geology and Paleontology Survey and Exploration Center—described how surface fossils assemble a portrait of Tethyan marine ecology from ~46 million years ago.

“We may be able to assemble an image of the depositional environment and marine ecology of the Tethyan Sea in Saudi Arabia 45 million years ago.”

— Iyad S. Zalmout, SGS Paleontology technical adviser

• ◆Shark teeth abundant: Isurus, Cretolamna, Odontaspis, Galeocerdo, Carcharhinus
• ◆Ray fossils: sawfish, eagle rays, and knifetooth species
• ◆Bony fishes: extinct barracuda, saber-toothed herring, billfish, butterflyfish-like species
• ◆Molluscs, bivalves, solitary corals on shale beds
• ◆SGS developing Khurais as a natural paleontological reserve

SAPIENS · Wenner-Gren Foundation · 16 April 2020

Will Asia Rewrite Human History?

Al Wusta 1 — middle phalanx (finger bone) · ~87.6k ya · Al Wusta, Nefud Desert, Saudi Arabia

Walking through the Al-Wusta dig site in 2016, SGS paleontologist Iyad Zalmout spotted a tiny bone eroding from sediment. The 87,000-year-old intermediate phalanx—probably a middle finger—became the earliest directly dated Homo sapiens fossil outside Africa and the Levant, evidence that humans spread farther and faster than once thought.

• ◆Earliest directly dated Homo sapiens fossil outside Africa and the Levant
• ◆Uranium-series age 85.1–90.1 ka (~87,600 ± 2,500 years)
• ◆Intermediate phalanx 32.3 mm long—slender, unlike Neanderthal digits
• ◆Enthesophyte records repeated physical stress on hands
• ◆380 stone tools and 800+ animal fossils at a Pleistocene lake shore
• ◆Wet grassland with hippos and African antelope—not today's desert
• ◆Evidence humans spread farther and faster than previously thought

“We knew it [was] important. It was the first direct evidence of any large primate or hominid life in the area.”

— Iyad S. Zalmout

Ars Technica · 9 April 2018

History gives us the finger

Saudi Arabian fossil find puts finger on the story of human dispersal

Around 84,000 years ago, stronger monsoons transformed Arabia into a grassland dotted with lakes. Al-Wusta was a shallow shore where hippos wallowed, African antelope grazed, and hunter-gatherer bands left 380 stone tools among 800+ animal fossils—the first site in the region with human remains.

“So actually it does all fit together very neatly, with Al-Wusta being an early representative of a much broader process.”

— Huw Groucutt

Haaretz · Archaeology · 9 April 2018

85,000-year-old Homo Sapiens Bone Found in Saudi Arabia Rewrites Human History

By Ruth Schuster

A single finger bone found in 2016 by Iyad S. Zalmout, paleontologist with the Saudi Geological Survey, has been definitively identified as Homo sapiens—changing the paradigm of migration out of Africa. Far from the sea, deep in today's Nefud desert, the find rejects the model of humans hugging coastlines while leaving Africa.

“The Al Wusta fossil proves modern humans reached Arabia by 90,000 years ago.”

— Michael Petraglia

“We view the 60,000-year-old exodus as one of many migrations out of Africa—hence the Arabian fossil supports a multiple migrations model out of Africa.”

— Michael Petraglia

General view of excavations at Al Wusta—the white ancient lakebed where hippos once lived, now ringed by sand dunes of the Nefud Desert.

Interdisciplinary surveys of palaeolake deposits in the western Nefud identified thousands of wetlands and 46 prehistoric archaeological sites—from Lower Palaeolithic to pre-Islamic Holocene—showing how episodic wet periods enabled human dispersal across Arabia's desert belt. Iyad S. Zalmout co-authored the interdisciplinary study with Huw S. Groucutt, Michael D. Petraglia, and Saudi colleagues—linking satellite-identified palaeolake deposits to archaeological and palaeontological assemblages across the desert belt.

• ◆Thousands of discrete palaeolakes and palaeowetlands mapped via satellite imagery
• ◆46 prehistoric sites linked to freshwater deposits
• ◆Lower Palaeolithic sites concentrated near raw material at the Nefud fringe
• ◆Middle Palaeolithic occupations extend deeper into the dune field
• ◆First Neolithic hearth complexes documented deep within the dunes
• ◆Western Nefud may have offered more reliable water than elsewhere in northern Arabia

The survey contextualizes later discoveries such as the Al Wusta Homo sapiens finger bone—evidence that wet Pleistocene grasslands and lakes once transformed landscapes now dominated by sand.

Following the water

Lacustrine deposits across the Nefud preserve evidence of Green Arabia—episodic wet intervals when lakes, wetlands, and savanna-like ecosystems enabled hominin dispersal long before today's hyper-arid desert. Teams have surveyed lacustrine deposits across Great Nefud Desert · ~70,000 km² northern Saudi Arabia—depressions that once held lakes, wetlands, and African-like savannas during Green Arabia wet phases.

• ◆Ancient palaeolakes visible as distinct lacustrine deposits amid red dunes
• ◆Ti's al Ghadah: first dated middle Pleistocene fauna in Arabia
• ◆Al Wusta 2016: only direct human fossil in region at ~90 ka
• ◆Centripetal Levallois technology at Al Wusta—Middle Paleolithic
• ◆Arabian Peninsula as corridor for repeated out-of-Africa dispersals

Griffith University · PLOS ONE · 17 April 2024

First evidence of human occupation in lava tube cave in Saudi Arabia

Umm Jirsan · Neolithic · Chalcolithic · Bronze Age · ~10,000–3,500 years ago

In Harrat Khaybar's volcanic landscape, interdisciplinary excavations revealed the first evidence of human occupation in an Arabian lava tube. Iyad Zalmout co-authored the PLOS ONE study with Griffith University's ARCHE team, SGS colleagues, and international partners—uncovering pastoral routes, rock art, and isotopic records spanning millennia.

• ◆First comprehensive lava-tube archaeology study in Saudi Arabia
• ◆Repeated occupation from Neolithic through Chalcolithic/Bronze Age
• ◆Pastoral route linking key oases—rock art of cattle, sheep, goats, dogs
• ◆Isotopes show livestock grazing wild grasses; humans high in protein
• ◆Increasing C3 plant consumption—possible emergence of oasis agriculture

“Our findings at Umm Jirsan provide a rare glimpse into the lives of ancient peoples in Arabia, revealing repeated phases of human occupation and shedding light on the pastoralist activities that once thrived in this landscape.”

— Mathew Stewart, Griffith University ARCHE

Journal of Vertebrate Paleontology · September 2024

Inabtanin alarabia

Tal Inab, Jordan · Maastrichtian · Upper Cretaceous

Grape-dragon (inab + tanin) from Tal Inab · alarabia references the Arabian Peninsula

Two large azhdarchoid pterosaurs with three-dimensionally preserved wing elements from Jordan—Inabtanin alarabia (~5 m wingspan) and Arambourgiania philadelphiae (~10 m)—reveal contrasting flight mechanics via micro-CT of humeral internal structure. Iyad S. Zalmout co-authored the study with Kierstin Rosenbach, Danielle Goodvin, Jordanian colleagues, and Jeffrey A. Wilson Mantilla—comparing micro-CT scans of humeri from Inabtanin alarabia and Arambourgiania philadelphiae to extant birds.

• ◆First new Jordan pterosaur species in decades—Inabtanin alarabia
• ◆Hollow strut morphology in Inabtanin—like flapping birds
• ◆Helical cortical ridges in Arambourgiania—like soaring birds
• ◆Rare 3D-preserved pterosaur wing bones from Afro-Arabia
• ◆Named for Tal Inab (grape hill) geomorphology near the locality

Proceedings of the Royal Society B · 26 August 2021

Phiomicetus anubis

Gehannam Formation · Middle Eocene · Lutetian · Gehannam Formation, Fayum Depression, Egypt

A new medium-sized protocetid preserving skull and mandible reveals a strong raptorial feeding style—and nests as the most basal protocetid known from Africa, co-occurring with the remingtonocetid Rayanistes afer. Iyad S. Zalmout co-authored the description with Abdullah Gohar, Mohammed Antar, Robert Boessenecker, Erik Seiffert, and Hesham Sallam—recovering Africa's most basal known protocetid from the same bed as Rayanistes afer.

• ◆Most basal African protocetid in phylogenetic analysis
• ◆Enlarged temporal fossae and raptorial jaw mechanics
• ◆Co-occurrence with remingtonocetid Rayanistes afer in same bed
• ◆First clear evidence both families shared African ecosystems
• ◆Four webbed limbs—semi-aquatic stage of whale evolution

SBS News · 10 January 2019

Scientists find remains of a whale inside bigger whale

Basilosaurus isis · Wadi Al Hitan (Valley of the Whales), Egypt · ~35 Ma

Stomach contents of a 15-meter Basilosaurus isis from Egypt's Valley of the Whales reveal apex predation—sharks and large bony fish, but predominantly bones of the smaller archaeocete Dorudon atrox. Jordanian palaeontologist Iyad Zalmout helped excavate remains in Egypt's Valley of the Whales—a shallow late Eocene sea where the 15-meter predator fed predominantly on Dorudon atrox.

• ◆Whale-on-whale predation ~35 million years before orcas
• ◆Bite marks on prey skulls—live hunting, head-first attacks
• ◆Shallow Tethys may have been a Dorudon nursery and hunting ground
• ◆Compared to modern killer whale feeding on smaller whales and calves
• ◆Strengthens evidence Basilosaurus was an apex marine predator