He bases this principal on the fact that before live Coelacanths were found, they were thought to have been extinct for 60-70 million years. Despite this, no fossils between that putative time period and today have been found. Yet the Coelacanth exists today.
Dinosaurs found above the K/T line were once considered reworked,which means the fossils were eroded and then redeposited into younger strata.Scientists never provided any evidence of reworking,though.It was just an excuse to preserve the current model.New evidence has forced them to realize that dinosaurs did survive at least 500,000 years after the K/T boundary.
New evidence suggests an "isolated community" escaped annihilation and lived on a rocky, desert plateau in North America.
Until now, palaeontologists widely believed the creatures were wiped out 65 million years ago when an asteroid collided with Earth.
Carbon dating of newly-discovered bones in the San Juan Basin proves that these lived for another half-a-million years.
I think they are wrong about the carbon dating part because carbon dating could'nt possibily work on such an old timescale,but it does show how assumptions based on fossils are always being revised and far from conclusive.Paleoentology is a historical science and not an empirical one.
Why the gap? Of course, this argument is only strengthened by the ever-mounting number of 'living fossils' that exist.
Here is a list of some living fossils from wiki.Plants
Amborellaceae Ã¢â‚¬â€œ a plant from New Caledonia, possibly closest to base of the flowering plants
Araucaria araucana Ã¢â‚¬â€œ the Monkey Puzzle tree
Ginkgo tree (Ginkgoaceae)
Horsetails Ã¢â‚¬â€œ Equisetum (Equisetaceae)
Metasequoia Ã¢â‚¬â€œ Dawn Redwood (Cupressaceae; a borderline example, related to Sequoia and Sequoiadendron)
Sciadopitys tree (Sciadopityaceae)
Whisk ferns Ã¢â‚¬â€œ Psilotum (Psilotaceae)
Wollemia tree (Araucariaceae Ã¢â‚¬â€œ a borderline example, related to Agathis and Araucaria) Fungi
Aardvark (Orycteropus afer)
Cypriot mouse (Mus cypriacus)
Red Panda (Ailurus fulgens)
Okapi (Okapia johnstoni)
Koala (Phascolarctos cinereus)
Laotian Rock Rat (Laonastes aenigmamus)
Volcano rabbit (Romerolagus diazi)
Amami rabbit (Pentalagus furnessi)
Iriomote cat (Prionailurus iriomotensis)
Monito del Monte (Dromiciops gliroides)
monotremes (the platypus and echidna)
Mountain Beaver (Aplodontia rufa)
Przewalski's Horse (Equus ferus przewalskii, Equus przewalskii or Equus caballus przewalskii, classification is debatedBirds
Acanthisittidae (New Zealand "wrens") Ã¢â‚¬â€œ 2 living species, a few more recently extinct. Distinct lineage of Passeriformes.
Hoatzin (Ophisthocomus hoazin) Ã¢â‚¬â€œ One living species. Distinct lineage of Neoaves.
Broad-billed Sapayoa (Sapayoa aenigma) Ã¢â‚¬â€œ One living species. Distinct lineage of Tyranni.
Bearded Reedling (Panurus biarmicus) Ã¢â‚¬â€œ One living species. Distinct lineage of Passerida or Sylvioidea.
Coliiformes (mousebirds) Ã¢â‚¬â€œ 6 living species in 2 genera. Distinct lineage of Neoaves.
Magpie-goose (Anseranas semipalmata) Ã¢â‚¬â€œ One living species. Distinct lineage of Anseriformes. Reptiles
Crocodilia (crocodiles, gavials and alligators)
Tuatara (Sphenodon punctatus and Sphenodon guntheri) Amphibians
Purple frog (Nasikabatrachus sahyadrensis) Bony fish
Bowfin (Amia calva)
Coelacanth (the lobed-finned Latimeria menadoensis and Latimeria chalumnae)
Queensland lungfish (Neoceratodus fosteri)
Sturgeons and paddlefish (Acipenseriformes) Sharks
Frilled shark (Chlamydoselachus anguineus) Insects
Mantophasmatodea (gladiators; a few living species)
Mymarommatid wasps (10 living species in genus Palaeomymar)
Nevrorthidae (3 species-poor genera)
Notiothauma reedi (a scorpionfly relative)
Orussidae (parasitic wood wasps; about 70 living species in 16 genera)
Peloridiidae (peloridiid bugs; fewer than 30 living species in 13 genera)
Sikhotealinia zhiltzovae (a jurodid beetle)
Syntexis libocedrii (Anaxyelidae cedar wood wasp) Crustaceans
glypheoid lobsters (3 living species: Neoglyphea inopinata, N. neocaledonica, and Laurentaeglyphea neocaledonica)
Stomatopods (Mantis shrimp)
Triops cancriformis (also known as Tadpole shrimp) (a notostracid crustacean) Molluscs
Nautilina (e.g. Nautilus pompilius)
Neopilina galateae, a monoplacophorid mollusc
Ennucula superba (Nut clam) Other invertebrates
Horseshoe crabs (only 4 living species of the class Xiphosura, family Limulidae: Limulus polyphemus,Tachypleus gigas, Tachypleus tridentatus and Carcinoscorpius rotundicauda)
Lingula anatina (an inarticulate brachiopod)
Valdiviathyris quenstedti (a craniforman brachiopod)