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Mammoths appear in the fossil record. 4.5 Ma Marine iguanas diverge from land iguanas. 4 Ma Australopithecus evolves. Stupendemys appears in the fossil record as the largest freshwater turtle, first modern elephants, giraffes, zebras, lions, rhinoceros and gazelles appear in the fossil record 3.6 Ma Blue whales grow to modern size. 3 Ma ...
The Cambridge Encyclopedia of Human evolution. Cambridge University Press. ISBN 978-0-521-46786-5. (Note: this book contains very useful, information dense chapters on primate evolution in general, and human evolution in particular, including fossil history). Leakey, Richard & Lewin, Roger. Origins Reconsidered: In Search of What Makes us Human ...
Index fossils must have a short vertical range, wide geographic distribution and rapid evolutionary trends. Another term, "zone fossil", is used when the fossil has all the characters stated above except wide geographical distribution; thus, they correlate the surrounding rock to a biozone rather than a specific time period.
These cell-sized prokaryote fossils are seen in the Barberton fossil record in rocks as old as 3.5 billion years. [1] The Barberton Greenstone Belt is an excellent place to study the Archean Earth due to exposed sedimentary and metasedimentary rocks.
Fossils of the algae Grypania have been reported in 1.85 billion-year-old rocks (originally dated to 2.1 Ga but later revised [15]), indicating that eukaryotes with organelles had already evolved. [144] A diverse collection of fossil algae were found in rocks dated between 1.5 and 1.4 Ga. [145] The earliest known fossils of fungi date from 1.43 ...
c. 315 Ma – The evolution of the first reptiles. c. 312 Ma – Hylonomus makes first appearance, one of the oldest reptiles found in the fossil record. c. 306 Ma – Diplocaulus evolves in the swamps with an unusual boomerang-like skull. c. 305 Ma – First diapsids evolve; Meganeura, a giant dragonfly dominates the skies.
Fossils can be used to recognize rock layers of the same or different geologic ages, thereby coordinating locally occurring geologic stages to the overall geologic timeline. The pictures of the fossils of monocellular algae in this USGS figure were taken with a scanning electron microscope and have been magnified 250 times.
The Precambrian fossil record is poorer than that of the succeeding Phanerozoic, and fossils from the Precambrian (e.g. stromatolites) are of limited biostratigraphic use. [4] This is because many Precambrian rocks have been heavily metamorphosed , obscuring their origins, while others have been destroyed by erosion, or remain deeply buried ...