Most life-forms were single-celled, with no hard parts to fossilize.
Oxygen
Most rocks from that era are deeply buried.
Archeozoic and ProterozoicThe two periods of the Cenozoic Era are the Tertiary and the Quatemary.
It is best to break down the question into smaller parts.1) The Precambrian was the 1st Era? (FALSE)The Precambrian was a super-eon not an era. It was the 1st of the 2 Super-Eons.The 1st named era was the Eoarchean Era (3,800 - 3600 Ma). This was during the Archean Eon (3,800 - 2,500 Ma). This was proceeded by the Hadean Eon (4,600 - 3,800) but no Eras from this time have been named. These were all in the Precambrian Super-Eon (4,600 - 542 Ma).2) The Precambrian was the longest Era? (FALSE)The longest era also occurred in the Precambrian. This was the Paleoproterozoic Era (2,500 - 1,600 Ma) which lasted 900 million years.3) The Precambrian lasted 4 billion years (TRUE)The Precambrian was the longer of the 2 super-eons. It lasted from 4,500 to 542 million years ago, some 3.96 billion years, compared to the current super-eon that has lasted a mere 542 million years.4) During the Precambrian the Earth had no solid crust (FALSE)The Earth is approximately 4,600 million years old. According to the latest theory 4,530 a Mars sized planet called theia hit the earth causing the crust to in part or totally melt (It also gave rise to the moon). Estimates suggest that over the next 30 million years the crust was able to solidify so when the Precambrian Super-Eon started the crust was solid. Certainly by 3,500 million years ago there was life. Fossilized stromatolites have been found at this time. There is no known life that can survive at the temperates necessary for molten rock so the crust must have cooled and solidified by this time.
The Precambrian Era. The name means: "before the Cambrian period." This old, but still common term was originally used to refer to the whole period of earth's history before the formation of the oldest rocks with recognizable fossils in them. In the last few decades, however, geologists have found that there are some hard-to-discern fossils in some Precambrian rocks, so this period is now also known as the Cryptozoic or "obscure life" Eon (from the words "crypt" = "hidden," and "zoon" = "life"). The Precambrian covers almost 90% of the entire history of the Earth. It has been divided into three eras: the Hadean, the Archean and the Proterozoic. Source: Unknown The Precambrian Era comprises all of geologic time prior to 600 million years ago. The Precambrian was originally defined as the era that predated the emergence of life in the Cambrian Period. It is now known, however, that life on Earth began by the early Archean and that fossilized organisms became more and more abundant throughout Precambrian time. The two major subdivisions of the last part of the Precambrian are the Archean (oldest) and the Proterozoic. Rocks younger than 600 Ma are considered part of the Phanerozoic.
Most life-forms were single celled, with no hard parts to fossilize.
Most life-forms were single celled, with no hard parts to fossilize.
The main characteristic that distinguishes the fossil record of the Paleozoic Era from the Precambrian Era is the appearance of diverse and complex multicellular organisms in the Paleozoic Era. In the Precambrian Era, the fossil record primarily consists of simpler single-celled organisms. Additionally, the Cambrian Explosion, which occurred at the beginning of the Paleozoic Era, marked a significant increase in the diversity of life forms.
During the Precambrian times, life was mostly limited to single celled organisms. Life that was not single cellular didn't have any hard body part (like teeth, bones, shells, etc.) and so they weren't preserved.
Abundant and diverse fossils first appeared in the Cambrian era, although there is fossil evidence throughout much of the Precambrian.
The Precambrian is a long period and just as Earth has many climates now, it had many then.
The Precambrian era spanned approximately 4 billion years, making it the longest geologic time period in Earth's history.
the Precambrian era
**Precambrian**
The Precambrian Era ended with the beginning of the Cambrian Period, approximately 541 million years ago. This period is characterized by the sudden appearance of a diverse range of complex life forms in the fossil record, known as the "Cambrian explosion".
There are many different types of cyanobacteria. We are just now beginning to discover how many exist in a drop of seawater. We have no idea how many existed in the Precambrian era.
The two subdivisions of the Precambrian Era are the Hadean and the Archean Eons.