419 — 359 Ma

Devonian

Fish dominate the seas while the first forests and amphibians conquer the land.

Oceans

Middle Devonian Stromatoporoid and Coral Reef Crest

In a warm, shallow Middle Devonian sea about 393–383 million years ago, a surge-swept reef crest is built by domed stromatoporoid sponges such as Stromatopora, branching Amphipora, and colonial corals including Favosites, with scattered horn corals like Heliophyllum rising from pale carbonate rubble. Small Phacops trilobites crawl across the seafloor, dwarfed by the meter-scale reef framework that dominated many tropical epicontinental seas of the time. Before modern coral reefs became widespread, stromatoporoid–coral communities like these formed some of the great reef systems of the Devonian, often called the “Age of Fishes.”

Late Devonian Dunkleosteus Hunting Cladoselache Sharks

In the Late Devonian, about 372–359 million years ago, a giant armored fish, Dunkleosteus terrelli, surges through the dim outer-shelf seas of tropical Laurussia in pursuit of a scattering school of Cladoselache. The scene captures a vertebrate-dominated ocean in transition: swift early sharks, drifting ammonoids such as Manticoceras, and murky, particle-rich water above deeper oxygen-poor basins where organic-rich muds accumulated. Rather than true teeth, Dunkleosteus wielded sharpened bony jaw blades, making it one of the most formidable marine predators of its time.

Middle Devonian Crinoid Meadow on Carbonate Shelf

In the warm, clear seas of the Middle Devonian, about 393–383 million years ago, dense meadows of stalked crinoids such as Cupressocrinites and Taxocrinus rose from a pale carbonate shelf, their feathery crowns filtering food from gentle currents. Around their bases lie shell beds of brachiopods including Mucrospirifer and Atrypa, while small Platyceras snails cling near some crinoid calyxes, illustrating a well-known Paleozoic ecological association. This scene captures a typical shallow tropical shelf community of the Devonian, when echinoderms, brachiopods, stromatoporoids, and corals flourished in greenhouse seas long before the first marine reptiles or modern seagrass evolved.

Late Devonian Anoxic Basin and Black Shale Formation

In this Late Devonian marine basin, about 372–359 million years ago, dim green-black water settles over a broad seafloor of fine organic mud destined to become black shale. Sparse radiolarians drift in the water column above laminated, pyrite-rich sediment, while the near absence of burrows or bottom-dwelling life reveals severe oxygen depletion during one of the Devonian’s recurrent oceanic crises. The faintly visible shelf margin above hints at a warmer, reef-fringed world nearby, but the basin interior itself is quiet, stagnant, and ecologically stressed.

Late Devonian Archaeopteris Forest Estuary on Laurussia

Along a humid Late Devonian estuary on the margin of Laurussia, some of Earth’s first forests send muddy, tannin-stained runoff into a warm shallow sea about 380–360 million years ago. Towering Archaeopteris trees and smaller cladoxylopsids such as Wattieza line silty channels, while low Drepanophycus covers wet banks and driftwood gathers on tidal flats. This kind of forested delta helped transform Devonian coastal oceans by increasing sediment and nutrient delivery, linking the rise of land plants with changing marine ecosystems where early fishes, including small bony fishes and placoderms, cruised the brackish shallows.

Tiktaalik Roseae in Late Devonian Tidal Shallows

In a Late Devonian tidal creek about 375 million years ago, the stem tetrapod Tiktaalik roseae lies half-submerged in brackish, tea-brown water, its flat head, upward-facing eyes, and sturdy, wrist-like pectoral fins revealing adaptations for life in extremely shallow channels. The muddy banks are lined with early vascular plants and woody debris from some of Earth’s first forested landscapes, reflecting a coastal world where land and sea were becoming increasingly connected. This scene captures a pivotal stage in vertebrate evolution, when lobe-finned fishes were beginning to exploit the margins between water and land.

Tropical Storm Over Devonian Carbonate Reef Shelf

A tropical epicontinental sea in the Middle to Late Devonian, roughly 390–370 million years ago, is shown under the violence of a major storm as waves crash across a stromatoporoid–coral reef rim and sediment-choked lagoon waters swirl behind it. The reef is built not by modern corals, but by stromatoporoid sponges together with tabulate and rugose corals, while scattered placoderm fishes, early sharks, and orthocone cephalopods inhabit the waters beyond the breakers. Low carbonate islands on the shelf support only early vascular plants—lycopsids, zosterophyll-like vegetation, and progymnosperm growth—reflecting a time when the first expanding land floras were beginning to alter erosion, runoff, and shallow-marine ecosystems.

Coastal Forests

Archaeopteris trees in a misty Devonian estuary dawn

In this Late Devonian estuary of Laurussia, about 370–360 million years ago, towering Archaeopteris—among the first true trees—rise from silty natural levees above misty brackish channels. In the shallow water, small armored Bothriolepis placoderms patrol the muddy bottom with their distinctive jointed pectoral appendages, while low lycopsid thickets and other primitive land plants form a sparse understory. The scene captures one of Earth’s earliest forested coastal landscapes, where deep-rooted trees were beginning to transform soils, waterways, and the planet’s atmosphere.

Tiktaalik roseae hunting in a Devonian tidal channel

In a Late Devonian tidal channel on the low coastal plains of Laurussia, about 375 million years ago, Tiktaalik roseae surges from shallow brackish water toward a shoal of small ray-finned fishes. Its broad flattened head, upward-facing eyes, and sturdy fin-limbs—capable of propping the body at the water’s edge—highlight the remarkable mix of fish and early tetrapod features that made Tiktaalik a key transitional form. Along the muddy bank, rooted Archaeopteris and other early vascular plants reveal one of Earth’s first forested landscapes, where evolving vertebrates were beginning to exploit the boundary between water and land.

Trigonotarbid arachnid on a damp Devonian forest floor

On a damp Devonian forest floor, a trigonotarbid arachnid stalks tiny wingless hexapods across waterlogged mud strewn with woody debris, low bryophyte-like mats, juvenile lycopsids related to Drepanophycus, and forked sprays of Hyenia. This scene represents one of Earth’s earliest true forests on the coastal lowlands of Laurussia during the Middle to Late Devonian, roughly 390–370 million years ago, when open stands of Archaeopteris-like trees and other primitive vascular plants were beginning to transform soils, habitats, and terrestrial food webs.

Storm flood inundating a Devonian Archaeopteris coastal forest

In this Late Devonian coastal forest of Laurussia, about 370–360 million years ago, heavy rain and a marine-incursion flood spread reddish silt through a flat, forested floodbasin. Medium-sized Archaeopteris trees, among the earliest deep-rooted woody plants, rise from muddy banks with exposed roots gripping the sediment, while patchy lycopsids and other primitive understory plants occupy the saturated lowland. In the murky overflow channels, a large lobe-finned fish and an early tetrapodomorph—still fish-like, with a flattened head and robust fins rather than true limbs—hint at the evolutionary experiments unfolding along Devonian shorelines.

Pterygotus sea scorpion in a Devonian brackish creek

In a murky brackish creek on the Laurussian coastal plain, a giant sea scorpion, Pterygotus, cruises just above ripple-marked mud while a small armored placoderm, Bothriolepis, probes the sediment below and tiny ostracods drift nearby. This scene represents a Late Devonian estuarine wetland about 380–360 million years ago, when some of Earth’s first forests—sparse stands of Archaeopteris and other seedless plants—lined low, muddy shorelines. Eurypterids such as Pterygotus were among the top aquatic predators of these tidal channels, hunting in waters shaped by sediment, roots, and the early spread of deep-rooting vegetation.

Stromatoporoid and coral patch reef in Devonian seas

A Late Devonian patch reef flourishes in warm, shallow seas about 380–370 million years ago, just offshore from the earliest forested coastal plains of Laurussia. Bulbous stromatoporoids and honeycomb colonies of Favosites build the reef framework, while horn corals, lace-like bryozoans, stalked crinoids, and wing-shaped brachiopods such as Mucrospirifer crowd the hard surfaces and shell-strewn sediment. On the carbonate rubble below, Phacops trilobites crawl among broken coral fragments, illustrating the rich invertebrate communities that thrived in Devonian reef ecosystems before their decline near the end of the period.

Dunkleosteus placoderm patrolling a Late Devonian reef margin

At the edge of a Late Devonian reef, about 372–359 million years ago, a giant armored placoderm, Dunkleosteus terrelli, cruises above the shelf margin while smaller Cladoselache sharks wheel below and tiny ammonoids such as Tornoceras drift in the hazy water. The seafloor is built not by modern corals but by stromatoporoids and tabulate and rugose corals, reflecting the distinctive reef ecosystems of Devonian seas along Laurussia. Suspended organic particles and soft blue-green light hint at nearby forested coastlines, where Earth’s earliest trees were beginning to transform both land and sea.

Gondwana

Late Devonian Malvinokaffric shelf brachiopod seafloor

On a cool, storm-swept shallow shelf along southern Gondwana in the Late Devonian, about 380–360 million years ago, dense carpets of small brachiopods such as Australospirifer and Leptaena cover the seafloor between patches of dark mud and ripple-washed sand. Trilobites including Metacryphaeus and Burmeisteria crawl among the shells in the green-gray water, representing the distinctive cold-water Malvinokaffric fauna that inhabited high-latitude seas far from the tropical reef belts of the time. The subdued light, sparse community structure, and lack of corals or other warm-water organisms reflect the cooler marine conditions typical of this southern realm.

Late Devonian Gogo reef lagoon tropical corals

In the Late Devonian, about 380 million years ago, a shallow lagoon within the famous Gogo reef complex of Western Australia teemed with life beneath clear tropical seas. Mound-like stromatoporoids and honeycomb colonies of the tabulate coral Favosites built the reef framework, while the lobe-finned fish Gogonasus cruised above the carbonate bottom and smaller armored placoderms such as Groenlandaspis maneuvered among the coral heads. This scene captures a rare Gondwanan reef ecosystem from the Frasnian Stage, when vertebrate life was diversifying in warm marine habitats long before the age of dinosaurs.

Mandageria predator hunting in Gondwana reef channel

At dusk along a Late Devonian reef-margin channel on the northern Australian margin of Gondwana, a predatory tetrapodomorph fish, Mandageria, lunges through a flashing school of small early ray-finned fishes while coiled Tornoceras ammonoids drift in the open water above. The scene is set about 370–360 million years ago among stromatoporoid sponges, tabulate corals, and solitary rugose corals—reef builders that dominated Devonian seas long before modern coral reefs evolved. Together these animals capture a world near the close of the “Age of Fishes,” when armored and lobe-finned vertebrates flourished in warm marine habitats.

Archaeopteris forest on Devonian Gondwana river floodplain

In this Devonian floodplain scene from Gondwana, about 385–365 million years ago, a broad meandering river winds across red-brown mudflats lined by some of the earliest true forests. Scattered Archaeopteris trees rise 10–20 meters above the levees, their fern-like crowns casting long shadows over patches of shrubby lycopsids and reedlike sphenopsid relatives rooted in wet sediment. Exposed roots, driftwood, seasonal pools, and desiccation-cracked mud capture a world in transition, when deep-rooted vascular plants were beginning to stabilize riverbanks and transform continental landscapes.

Arid Gondwana interior basin with early lycopsids

A dry interior basin of Devonian Gondwana, about 370–360 million years ago, is shown as a vast, dusty plain of cracked mudflats, ephemeral braided channels, and salt-stained sediment under a hazy sky. Sparse clumps of low zosterophylls and early lycopsids cling to damp channel margins, their simple branching stems and primitive spore-bearing structures reflecting the still-limited spread of land plants in high-latitude continental interiors. This reconstruction highlights a seasonally arid Gondwanan landscape far removed from the lush coal swamps more typical of later periods.

Gogonasus ambush hunting Bothriolepis in freshwater backwater

In a quiet Late Devonian backwater of Gondwana, about 380–360 million years ago, the armored placoderm Bothriolepis shuffles across silty mud while a larger lobe-finned predator, Gogonasus, lies in ambush among waterlogged plant debris and exposed roots. The scene captures a low-energy freshwater habitat typical of floodplains and oxbow pools, where tannin-dark water, early forests of Archaeopteris-like trees, and primitive lycopsids and fern-like plants framed ecosystems close to the evolutionary setting that produced the first tetrapod-like vertebrates.

Stormy Late Devonian Malvinokaffric shelf tidal flats

On a storm-lashed shoreline of high-latitude Gondwana in the Late Devonian, about 370–360 million years ago, dark waves churn across muddy tidal flats and low sandstone ledges of the cool-water Malvinokaffric shelf. Sparse early land plants—small lycopsids, zosterophyll-like forms, and low progymnosperm scrub—cling to the distant coastal plain, while debris and perhaps stranded placoderm fish or eurypterids mark the water’s edge. The scene captures a southern hemisphere coast very different from the lush tropical Devonian often imagined, shaped instead by cold-temperate seas, powerful storms, and distinctive Gondwanan marine ecosystems.

Ocean Depths

Dunkleosteus hunting Manticoceras in Late Devonian Laurussia

In the dim pelagic waters of the Late Devonian, about 372–359 million years ago, a giant armored placoderm, Dunkleosteus terrelli, surges through a small shoal of Manticoceras ammonoids while two sleek Cladoselache sharks bank nearby above a dark offshore basin. The scene captures a deeper Laurussian sea below normal wave base, where sinking organic debris and low-oxygen bottom waters were common, and powerful nekton hunted in the open water far above black shale–forming seafloors.

Anoxic Late Devonian seafloor with Buchiola bivalves

In this Late Devonian deep-basin scene, roughly 372–359 million years ago, the seafloor lies under dim, murky water as finely laminated black mud accumulates in an oxygen-poor basin during a Kellwasser-style anoxic episode. Sparse life clings to the sediment surface: small Buchiola bivalves rest on the unbioturbated shale, while a few phacopid trilobites such as Phacops remain largely motionless among pyrite-flecked mud and undisturbed carcasses. The image captures a world where low oxygen suppressed scavengers and burrowers, allowing organic-rich black shales to form and preserving a stark record of Late Devonian marine stress.

Spiriferid brachiopods and Asteropyge trilobites on Devonian slope

On a dim Late Devonian outer-shelf slope, clusters of long-winged spiriferid brachiopods such as Mucrospirifer and Cyrtospirifer rest on gray mud and calcareous shale while small Asteropyge trilobites move among shell debris and ostracod-rich sediment. A few tall Cupressocrinites crinoids rise above the low-relief seafloor, filtering sluggish bottom currents in weak blue light below normal wave base. This scene represents an oxygenated deep-shelf to upper-slope community about 372–359 million years ago, showing that Devonian deeper-water habitats could support diverse benthic life even beyond the famous reef systems.

Late Devonian reef margin with Favosites and stromatoporoids

At the sunlit edge of a Late Devonian reef, roughly 380–370 million years ago, a rigid framework of stromatoporoids and tabulate corals such as Favosites and Alveolites gives way to a steep fore-reef slope littered with fresh coral rubble. Solitary rugose corals, including Heliophyllum, rise from the settling carbonate debris while small coiled Agoniatites ammonoids and a larger straight-shelled orthoconic nautiloid drift above the dimming drop-off. The scene captures a warm tropical epicontinental sea where shallow reef builders graded into deeper, darker outer-shelf waters that could become increasingly oxygen-poor away from the reef crest.

Pelagic food web with conodonts in Devonian waters

In the sunlit upper waters of a Late Devonian offshore sea, about 372–359 million years ago, dense plankton blooms support a busy pelagic food web. Tiny zooplankton drift in shimmering blue-green water alongside radiolarians, while eel-like conodont animals and small spiny acanthodian fishes hunt in the illuminated surface layers above a much deeper basin. This scene captures a Devonian open ocean increasingly shaped by high productivity, where some of the earliest vertebrate predators fed on swarms of minute planktonic prey.

Archaeopteris forest delta meeting the Late Devonian sea

In the Late Devonian, about 375–360 million years ago, muddy rivers draining some of Earth’s first true forests spread dark, sediment- and plant-rich water into a warm epicontinental sea. Towering Archaeopteris trees, among the earliest large woody plants, rise above groves of the cladoxylopsid Wattieza along the delta plain, while logs, bark, and organic debris wash seaward toward offshore basins where oxygen-poor black shales could accumulate. This scene captures a pivotal moment in Earth history, when expanding forests began reshaping coastlines, soils, and even the chemistry of the oceans.

Acadian mountain runoff into the Late Devonian coast

A storm-darkened Late Devonian coast along eastern Laurussia, about 370 million years ago, channels red-brown silt, plant debris, and ash-rich sediment from Acadian uplands into a murky gray-green sea. Patchy early forests of Archaeopteris, lycopsids, and other primitive vascular plants line swollen river mouths, while offshore the plume-stained waters hint at dysoxic basin conditions typical of some Devonian shelves and basins. Small palaeoniscoid fishes and distant placoderms, including arthrodires, underscore a world in which tectonic uplift, expanding forests, and marine oxygen stress were becoming tightly linked.

Next Period

Carboniferous