1996: Scientists announced that a meteorite from Mars had been found in Antarctica, containing microfossils
provide high temporal resolution of environmental trends.
A single specimen of penaeid shrimp and numerous cancrid crabs, referred to Metacarcinus danai Nations, were collected in association with a mixed assemblage of terrestrial plants, a few bivalves, marine mammals, and numerous taxa of microfossils
. Living species of Metacarcinus are found in temperate, normal-marine conditions in water depths up to about 100 m.
The book includes various images - about 30 of which are colour - which show fossils and their living counterparts, microfossils
and their modern counterparts, and areas where the earliest evidence of life and environments have been discovered.
The blobs, say excited scientists, are microfossils
left by ancient bugs.
To be accepted as bona fide, ancient microfossils
must be structurally preserved biogenic remnants that are indigenous to and syngenetic with the primary deposition of sedimentary rocks of known stratigraphic and geographic source and established age (5, 14).
Permian plant microfossils
from the Flowerpot Formation, Greer County, Oklahoma.
When these bits of material were eventually studied by electron microscope, they showed themselves unmistakably to be microfossils
, or remnants of simple cells.
Paleontologists retrieve microfossils
from sediment samples with sieves, chemicals, filters, and centrifuges, in some cases recovering millions of tiny skeletons from a sample smaller than your thumb.
from the Upper Triassic of northeastern New Mexico.
For example, the earliest microfossils
show that life began on our planet 3.5 billion years ago, or only shortly after Earth's crust had cooled from its molten state.
With the help of microfossils
, the sediment layers where the skeleton was positioned were precisely dated to the middle Eocene, 42.6 million years ago.