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i wanted to find out why so many christians refuse the fact that transitional fossils exist and it proves that evolution is real. it also shows that the planet is much older than 8,000 years old.
below is a short list of animal (mammal) fossils that have been found.
this is from Talkorigins.com
Carnivores
Dogs:
i know there is a lot of data on this post, it is only a small portion of all the transitional fossils found.
below is a short list of animal (mammal) fossils that have been found.
this is from Talkorigins.com
Carnivores
- Creodonts -- early placental mammals with minor but interestingly carnivore-like changes in the molars and premolars. Had a carnivore- like shearing zone in the teeth, though the zone moved throughout life instead of staying in particular teeth. Also had a carnivore- like bony sheet in the brain dividing cerebrum & cerebellum, details of ankle. Closely related to & possibly ancestral to carnivores. The origin of the creodonts is unclear. They probably were derived from condylarths.
- Cimolestes (late Cretaceous) -- This creodont (?) lost the last molar & then later enlarged the last upper premolar and first lower molar. (In modern carnivores, these two teeth are very enlarged to be the wickedly shearing carnassial teeth, the hallmark of carnivores.) Still unfused feet & unossified bulla. This genus is probably ancestral to two later lines of Eocene carnivores called "miacoids". Miacoids were relatively unspecialized meat-eaters that seem to have split into a "viverravid" line (with cat/civet/hyena traits) and a "miacid" line (with dog/bear/weasel traits). These two lines may possibly have arisen from these slightly different species of Cimolestes:
- Cimolestes incisus & Cimolestes cerberoides (Cretaceous) -- These are two species that lost their third molar, and may have given rise to the viverravid line of miacoids (see Hunt & Tedford, in Szalay et al., 1993).
- Cimolestes sp. (Paleocene) -- A later, as yet unnamed species that has very miacid-like teeth.
- Simpsonictis tenuis (mid-Paleocene) -- A very early viverravid. The upper carnassial was large; the lower carnassial was of variable size in different individuals.
- Paroodectes, Vulpavus (early Eocene) -- Early miacids. Enlarged carnassials now specialized for shearing. Still had unfused foot bones, short limbs, plantigrade feet, unossified bulla.
- Viverravus sicarius (mid-Eocene) -- Hunt & Tedford (in Szalay et al., 1993) think this viverravid may be the ancestral aeluroid. It has teeth & skeletal traits similar to the first known Oligocene aeluroids (undifferentiated cat/civet/hyenas).
Dogs:
- Cynodictis (late Eocene) -- First known arctoid (undifferentiated dog/bear).
- Hesperocyon (early Oligocene) -- A later arctoid. Compared to miacids like Paroodectes, limbs have elongated, carnassials are more specialized, braincase is larger. From here, the main line of canid evolution can be traced in North America, with bears branching out into a Holarctic distribution.
- Cynodesmus (Miocene) -- First true dog. The dog lineage continued through Tomarctus (Pliocene) to the modern dogs, wolves, & foxes, Canis (Pleistocene).
- Cynodictis (see above)
- Hesperocyon (see above)
- Ursavus elmensis (mid-Oligocene) -- A small, heavy doglike animal, intermediate between arctoids and bears. Still had slicing carnassials & all its premolars, but molars were becoming squarer. Later specimens of Ursavus became larger, with squarer, more bear-like, molars.
- Protursus simpsoni (Pliocene; also "Indarctos") -- Sheepdog-sized. Carnassial teeth have no shearing action, molars are square, shorter tail, heavy limbs. Transitional to the modern genus Ursus.
- Ursus minimus (Pliocene) -- First little bear, with very bearlike molars, but still had the first premolars and slender canines. Shows gradual tooth changes and increase in body size as the ice age approached. Gave rise to the modern black bears (U. americanus & U. thibetanus), which haven't changed much since the Pliocene, and also smoothly evolved to the next species, U. etruscus:
- Ursus etruscus (late Pliocene) -- A larger bear, similar to our brown bear but with more primitive dentition. Molars big & square. First premolars small, and got smaller over time. Canines stouter. In Europe, gradually evolved into:
- Ursus savini (late Pleistocene, 1 Ma) -- Very similar to the brown bear. Some individuals didn't have the first premolars at all, while others had little vestigial premolars. Tendency toward domed forehead. Slowly split into a European population and an Asian population.
- U. spelaeus (late Pleistocene) -- The recently extinct giant cave bear, with a highly domed forehead. Clearly derived from the European population of U. savini, in a smooth transition. The species boundary is arbitrarily set at about 300,000 years ago.
- U. arctos (late Pleistocene) -- The brown ("grizzly") bear, clearly derived from the Asian population of U. savini about 800,000 years ago.. Spread into the Europe, & to the New World.
- U. maritimus (late Pleistocene) -- The polar bear. Very similar to a local population of brown bear, U. arctos beringianus that lived in Kamchatka about 500,000 years ago (Kurten 1964).
i know there is a lot of data on this post, it is only a small portion of all the transitional fossils found.