Precambrian* –
all the time prior to the start of the Cambrian
(not a formal era/eon name) * synonymous with “Cryptozoic” – Greek for “hidden life” Proterozoic eon – Greek for “former life”
What does the word Precambrian actually mean?
: of,
relating to, or being the earliest era of geologic history or the corresponding system of rocks
that is characterized especially by the appearance of single-celled organisms and is equivalent to the Archean and Proterozoic eons — see Geologic Time Table.
Where does the word Precambrian originate?
The Precambrian is so named
because it preceded the Cambrian, the first period of the Phanerozoic Eon, which is named after Cambria
, the Latinised name for Wales, where rocks from this age were first studied. The Precambrian accounts for 88% of the Earth's geologic time.
What is meant by Precambrian time?
The Precambrian is the earliest of the geologic ages, which are marked by different layers of sedimentary rock. Laid down over millions of years, these rock layers contain
a permanent record of the Earth's past
, including the fossilized remains of plants and animals buried when the sediments were formed.
What does Phanerozoic mean in Greek?
History and Etymology for Phanerozoic
Greek phanerós
“visible, conspicuous”
(from phan-, base of phaínomai, phaínesthai “to become visible, come to light, appear” + -eros, adjective suffix) + -o- + -zoic entry 2 — more at fantasy entry 1.
What era do we live in?
Officially, we live in the Meghalayan age (which began 4,200 years ago) of
the Holocene epoch
. The Holocene falls in the Quaternary period (2.6m years ago) of the Cenozoic era (66m) in the Phanerozoic eon (541m).
What animals lived in Precambrian time?
The fossil record of multi-celled animals from the Precambrian includes three main groups that have persisted to the present day. These include the
sponges
, the cnidarians (including sea anemones, corals, and jellyfish) and the annelids, or segmented flatworms. Figure 1. Stromatolites and Precambrian prokaryotes.
Is nearly 90 percent of Earth's history?
The PRECAMBRIAN era
encompasses 90 percent of Earth's history.
What is the oldest era of Earth?
The oldest is
the Paleozoic Era
, which means “ancient life.” Fossils from the Paleozoic Era include animals and plants that are entirely extinct (e.g., trilobites) or are rare (e.g., brachiopods) in the modern world.
Was there life in the Precambrian era?
The early, Precambrian continents were unlike those we know today: they were smaller and had surfaces of igneous rocks.
No life lived upon them.
What does Cambrian mean in English?
1 : welsh. 2 : of, relating to, or being
the earliest geologic period of the Paleozoic era
or the corresponding system of rocks marked by fossils of nearly every major invertebrate animal group — see Geologic Time Table.
What does Paleozoic mean in Greek?
The Greek root zo- means
“life
,” so names such as Paleozoic were invented to refer to a period in the development of animal life. For geologists, the Paleozoic era is followed by the Mesozoic (meso- meaning “middle”), which is followed by the Cenozoic (ceno- meaning “recent”).
Which era is the shortest?
Quaternary Period
The Quaternary spans from 2.58 million years ago to present day, and is the shortest geological period in the Phanerozoic Eon. It features modern animals, and dramatic changes in the climate. It is divided into two epochs: the Pleistocene and the Holocene.
What does Helios mean?
Helios, (Greek:
“Sun”
) in Greek religion, the sun god, sometimes called a Titan. … From the 5th century bce, Apollo, originally a deity of radiant purity, was more and more interpreted as a sun god.
