Search results
Results from the WOW.Com Content Network
The history of life on Earth traces the processes by which living and extinct organisms evolved, from the earliest emergence of life to the present day. Earth formed about 4.5 billion years ago (abbreviated as Ga, for gigaannum) and evidence suggests that life emerged prior to 3.7 Ga. [1] [2] [3] The similarities among all known present-day species indicate that they have diverged through the ...
First signs of teeth in fish. Earliest Nautilida, lycophytes, and trimerophytes. 488–400 Ma First cephalopods [78] and chitons. [79] 395 Ma First lichens, stoneworts. Earliest harvestmen, mites, hexapods (springtails) and ammonoids. The earliest known tracks on land named the Zachelmie trackways which are possibly related to icthyostegalians.
Nov. 13—ALPINE — Two Texas universities are partnering with state and federal agencies to study the transboundary movements of black bears and mountain lions along the U.S.-Mexico border in ...
Stone tools found at the Shangchen site in China and dated to 2.12 million years ago are considered the earliest known evidence of hominins outside Africa, surpassing Dmanisi hominins found in Georgia by 300,000 years, although whether these hominins were an early species in the genus Homo or another hominin species is unknown.
Studies show that the pre-modern migration of human populations begins with the movement of Homo erectus out of Africa across Eurasia about 1.75 million years ago. Homo sapiens appeared to have occupied all of Africa about 150,000 years ago; some members of this species moved out of Africa 70,000 years ago (or, according to more recent studies, as early as 125,000 years ago into Asia, [1] [2 ...
Population movements of the proto-historical or early historical period include the Migration period, followed by (or connected to) the Slavic, Magyar, Norse, Turkic and Mongol expansions of the medieval period. The last world regions to be permanently settled were the Pacific Islands and the Arctic, reached during the 1st millennium AD.
Early modern human expansion in sub-Saharan Africa appears to have contributed to the end of late Acheulean industries at about 130,000 years ago, although very late coexistence of archaic and early modern humans, until as late as 12,000 years ago, has been argued for West Africa in particular.
Earth is the only place in the universe known to harbor life, where it exists in myriad environments. [8] [9] The origin of life on Earth was at least 3.5 billion years ago, possibly as early as 3.8-4.1 billion years ago. [2] [3] [4] Since its emergence, life has persisted in several geological environments.