The New Dinosaurs: An Alternative Evolution

The New Dinosaurs: An Alternative Evolution (1988) is a book written by geologist and paleontologist Dougal Dixon. While Dixon's earlier book After Man is set fifty million years in the future, The New Dinosaurs speculates on how the dinosaurs would have evolved over the last 65 million years had the Cretaceous-Tertiary extinction event not taken place.

The book contains a few suggestions inconsistent with current scientific knowledge. Pterosaurs and feathered dinosaurs replace birds in dominance, even though fossil evidence proves both groups (apart from maniraptora) were declining rapidly before the mass extinction took place. Dinosaurs were also filling the roles that mammals and squamates occupied during the dinosaur age, and most of the dinosaurs were covered with hair. Meanwhile, plesiosaurs seem to replace mosasaurs, despite the fact the latter were replacing the former in the late Cretaceous. All of these "mistakes" in the book are more likely just concurrent with the evidence and theories at the time of publishing, or perhaps the alternative evolution in the book began far earlier than assumed.

A detailed critic on the Speculative Evolution Forum can be found here.

An advanced version of this same concept (called The Speculative Dinosaur Project) is represented by a group of paleoartists in recent years. This hypothesis was collected at but they're offline now, there's another, possibly unofficial site here.

Ammonites

 * Coconut Grab, Nuctoceras litureperus, an ammonite that crawls onto land to grab coconuts, similar to our robber crab. The coconut Grab can even climb trees (Oceania).
 * Kraken, Giganticeras fluitarus, a massive floating ammonite with a shell 13 feet in diameter. Its tentacles are covered with poisonous barbs like those of a jellyfish. These deadly tentacles spread out in an area of 67 feet in diameter. The kraken only fears the pelorus, who is immune to its poisonous stings.

Dinosaurs and birds

 * Balaclav, Nivesaurus yetiforme, a large mountain-dwelling thescelosaur (an American relative of hypsilophodonts). It feeds mostly on the sparse vegetation along mountain slopes (North America).
 * Bricket, Rubusaurus petasus, a deer-like hadrosaur (Eurasia).
 * Cutlasstooth, Caedosaurus gladiadens, a saber-toothed predatory dinosaur (South America).
 * Coneater, Strobofagus borealis, a large social hypsilophodont with an elongated snout to store large batteries of cheek teeth (Eurasia).
 * Crackbeak, Fortirostrum fructiphagum, an arboreal hypsilophodont that evolved specialized perching feet. They use their beaks for cracking seeds and fruit (Africa, Asia, and Australia).
 * Cribrum, Cribrusaurus rubicundus, a flamingo-like predatory dinosaur with slender teeth for straining soda lakes for microorganisms (Australia).
 * Debaril, Harenacurrerus velocipes, a small running and hopping hypsilophodont (Eurasia).
 * Dingum, Velludorsum venenum, a meter-long predatory dinosaur with sexual dimorphism. Males are partially quadrapedal with a sail atop its back. The rays in this sail are tipped with venomous barbs, containing poisons from consumed desert plants. Females are larger and look more like a typical predatory dinosaur (Australia).
 * Dip, Harundosaurus montanus, a fish-eating mountain-dwelling dinosaur (South America).
 * Flurrit, Labisaurus alatus, a gliding predatory dinosaur (Asia).
 * Footle, Currerus elegans, an agile squirrel-like two-legged arboreal predatory dinosaur (North America).
 * Gestalt, Formisaura delacasa, a colonial bone-headed dinosaur. They build fortresses in trees where the queen sits on eggs. Males serve as soldiers in the colonies (Eurasia).
 * Gimp, Melexsorbius parvus, a nectar-sipping arboreal dinosaur (South America).
 * Glub, Lutasaurus anacrusus, an aquatic hypsilophodont with no back legs (Asia).
 * Gourmand, Ganeosaurus tardus, a scavenging tyrannosaur with detachable jaws and no front limbs (South America).
 * Gwanna, Gryllusaurus flavus, a kangaroo-like relative of Iguanodon. It inhabits grasslands and deserts. It has two movable fingers with two stationary ones and a thumb spike (Australia).
 * Hanuhan, Grimposaurus pernipes, a fleet-footed rock-dwelling hypsilophodont (Asia).
 * Jinx, Insinusaurus strobofagoforme, a sickle-clawed predatory dinosaur that imitates the coneaters. It looks and smells like its prey so packs can wander into coneater herds and attack (Eurasia).
 * Lumber, Elephasaurus giganteus, a large sauropod with a small elephant-like trunk (South America).
 * Megalosaur, Megalosaurus modernus, a surviving carnosaur from the Mesozoic. It survives on an island off the coast of Africa and spends most of its life scavenging. A species of dwarf megalosaur inhabits small islands.
 * Monocorn, Monocornus occidentalis, a buffalo-like horned dinosaur (North America).
 * Mountain Leaper, Montanus saltus, an agile mountain-dwelling predatory dinosaur (North America).
 * Nauger, Picusaurus terebradens, a woodpecker-like arboreal predatory dinosaur (North America).
 * Northclaw, Monuncus cursus, a cheetah-like predatory dinosaur with a massive dagger-like claw on its right hand for stabbing prey (North America).
 * Numbskull, Sphaeracephalus riparus, a mountain-dwelling bone-headed dinosaur (Asia).
 * Pangaloon, Filarmura tuburostra, an armored insect-eating dinosaur (South America).
 * Pouch, Saccosaurus spp., a duck-like predatory dinosaur with webbed feet, a stiff tail, and a transparent throat pouch like that of a pelican (Australia).
 * Rajaphant, Gregisaurus titanops, a socially-sophisticated sauropod (Asia).
 * Sandle, Fususaurus foderus, a burrowing mole-like predatory dinosaur (Africa).
 * Scaly Glider, Pennasaurus volans, an arboreal dinosaur with a fan of plates along its sides for gliding (South America).
 * Springe, Necrosimulacrum avilaquem, a predatory dinosaur that attracts its prey by playing dead, then stabbing it with its sickle toe claws (North America)
 * Sprintosaur, Family Sprintosauridae, antelope-like hadrosaurs. They come in two types: short-tailed crested sprintosaurs and long-tailed sprintosaurs without crests (North America).
 * Taddey, Multipollex moffati, a panda-like hypsilophodont (Asia).
 * Taranter, Herbasaurus armatus, a desert-dwelling ankylosaur (Eurasia).
 * Titanosaur, Altosaurus maximus, one of the few sauropod dinosaurs on Earth. It survives on a large island off the coast of Africa, as well as some dwarf species on various small islands.
 * Tree Hopper, Arbrosaurus bernardi, an arboreal leaping predatory dinosaur (Africa).
 * Treepounce, Raminsidius jacksoni, an agile marten-like arboreal predatory dinosaur (North America).
 * Treewyrm, Arbroserpens longus, an arboreal snake-like dinosaur with a slender neck and no front legs (Asia).
 * Tromble, Gravornis borealis, a massive flightless grazing bird from the Arctic regions (Eurasia).
 * Tubb, Pigescandens robustus, a slow-moving koala-like hypsilophodont with a pot belly and short legs. Its tail is shorter than its ancestors. It eats mostly eucalyptus leaves (Australia)
 * Turtosaur, Turotosaurus armatus, an armored sauropod (South America).
 * Waspeater, Vespaphaga parma, a thick-scaled anteater-like predatory dinosaur that eats wasps (Africa).
 * Watergulp, Fluvisaurus hauristus, a manatee-like hypsilophodont (South America)
 * Whiffle, Adescator rotundus, a flightless insect-eating bird (Eurasia).
 * Wyrm, Vermisaurus perdebracchius, a snake-like predatory dinosaur with no arms, thick belly scales, and an armored head used as a shield when burrowing (Africa)

Mammals

 * Zwim, Naremys platycaudus, a swimming placental mammal (Eurasia).
 * Unnamed mountain mammal which the harridan is seen attacking.
 * Unnamed grassland mammal which one of the dingums is seen carrying.

Pterosaurs

 * Flarp, Vexillala robusta, a flightless grazing ostrich-like pterosaur (Africa)
 * Harridan, Harpyia latala, a large condor-like pterosaur (South America).
 * Kloon, Perdalus rufus, a small flightless moa-like pterosaur with no wings and flexible feet (New Zealand).
 * Lank, Herbafagus longicollum, a flightless giraffe-like pterosaur (Africa).
 * Paraso, Umbrala solitara, a solitary heron-like pterosaur (Asia).
 * Plunger, Pinala fusiforme, a penguin-like pterosaur.
 * Shorerunner, Brevalus insularis, a mobile island-dwelling pterosaur that behaves like a gull, beachcombing and eating the corpses of coconut grabs stranded on shore (Oceania).
 * Sift, Pterocolum rubicundum, a fine-toothed heron-like pterosaur (North America).
 * Soar, Cicollum angustualum, an albatross-like pterosaur.
 * Unnamed grassland pterosaur which the rajaphants are seen fighting.
 * Wandle, Pervagarus altus, a giant flightless moa-like pterosaur that lives in high altitude plains in small groups (New Zealand).

Plesiosaurs and pliosaurs

 * Birdsnatcher, Raperasaurus velocipinnus, a large bird-eating plesiosaur with an elongated neck.
 * Pelorus, Piscisaurus sicamalus, a fish-shaped pliosaur that eats fish. It also hunts the kraken and is one of the few predators that is immune to the kraken's venom.
 * Whulk, Insulasaurus oceanus, a plankton-eating pliosaur.