Chapter_18_Lecture
... • Correlation often relies upon fossils
Principle of fossil succession – fossil
organisms succeed one another in a definite
and determinable order, and therefore any
time period can be recognized by its fossil
...
Volcanoes and Igneous Activity Earth
... • Correlation of rock layers
• Matching of rocks of similar ages in different
regions is known as correlation
• Correlation often relies upon fossils
– William Smith (late1700s-early 1800s) noted that
sedimentary strata in widely separated areas could
be identified and correlated by their distinctiv ...
assignment on gey 402(micropalentology - abuad lms
... constantly are forming within each cell. As these platelets land on the bottom of the ocean, they
are slowly covered up with remains of other plants and animals and bits of mud and sand that
have washed out with the rivers of the world. At this point they are part of a mud or marl or
sandy clay. Eve ...
4th period
... (endoplasm) and outer (ectoplasm) parts
Skeletons are usually fused into one
beautiful piece
Possess many pseudopodia that look like
needles
Use their buoyancy in coasting ocean
currents to move around
Reproduce both sexually and asexually
Heliozoans
Very similar to radiolarians
Skeleton consists of ...
Lecture Outlines PowerPoint Chapter 11 Earth Science, 12e
... the use of instructors in teaching their courses and assessing student learning.
Dissemination or sale of any part of this work (including on the World Wide Web)
will destroy the integrity of the work and is not permitted. The work and materials
from it should never be made available to students exc ...
Chapter 11
... Fossils: evidence of past life
Remains or traces of prehistoric life
Types of fossils
• Petrified – cavities and pores are filled with
precipitated mineral matter
• Formed by replacement – cell material is
removed and replaced with mineral matter
• Mold – shell or other structure is buried
and th ...
The age of fossils can be determined using radiocarbon dating (also
... However, fossils of species that survived for a relatively short time can be used to match
isolated rocks: this technique is called biostratigraphy. For instance, the
extinct chordateEoplacognathus pseudoplanus has a short range in the MiddleOrdovician
period. If rocks of unknown age have traces of ...
Da Vinci (1452- 1519)
... • The strata of the Paris Basin were close to
horizontal.
• As of 1811, Cuvier and Brongniart employed
fossils but only in the few instances where
more obvious evidences of sequence were
absent.
• The title of their work was Géographie
Minéralogique: they meant the distribution of
"external" charact ...
The excretory systems
... • Rocks at the bottom of the gorge are 2,000 years old.
• Observation of the fossils in the rock layers suggests:
– fish were the first vertebrates to appear 500 million
years ago.
– reptiles appeared about 300 million years after the fish.
...
HOW ARE FOSSILS? OLD - Creation Resources Trust
... how long rocks take to form, and we have
already considered evidence that sediments
form very quickly. When we read in the
newspapers about new fossil discoveries
which are immediately assigned a date, it
should be obvious that these fossils have not
been scientifically dated. They are, in fact,
dat ...
Evolutionary Evidences
... (original Spanish), the Ice Maiden, the Lady of
Ampato and the Frozen Lady, this mummy is
unfortunately going through quite a difficult modern
life and not doing so well. In 2006 daily newspaper
El Comercio published that an expert from the U.S.
Smithsonian Institution who was vacationing in the
sou ...
Small shelly fauna
The small shelly fauna or small shelly fossils, abbreviated to SSF, are mineralized fossils, many only a few millimetres long, with a nearly continuous record from the latest stages of the Ediacaran to the end of the Early Cambrian period. They are very diverse, and there is no formal definition of ""small shelly fauna"" or ""small shelly fossils"". Almost all are from earlier rocks than more familiar fossils such as trilobites. Since most SSFs were preserved by being covered quickly with phosphate and this method of preservation is mainly limited to the Late Ediacaran and Early Cambrian periods, the animals that made them may actually have arisen earlier and persisted after this time span.Some of the fossils represent the entire skeletons of small organisms, including the mysterious Cloudina and some snail-like molluscs. However, the bulk of the fossils are fragments or disarticulated remains of larger organisms, including sponges, molluscs, slug-like halkieriids, brachiopods, echinoderms, and onychophoran-like organisms that may have been close to the ancestors of arthropods.One of the early explanations for the appearance of the SSFs – and therefore the evolution of mineralized skeletons – suggested a sudden increase in the ocean's concentration of calcium. However, many SSFs are constructed of other minerals, such as silica. Because the first SSFs appear around the same time as organisms first started burrowing to avoid predation, it is more likely that they represent early steps in an evolutionary arms race between predators and increasingly well-defended prey. On the other hand, mineralized skeletons may have evolved simply because they are stronger and cheaper to produce than all-organic skeletons like those of insects. Nevertheless, it is still true that the animals used minerals that were most easily accessible.Although the small size and often fragmentary nature of SSFs makes it difficult to identify and classify them, they provide very important evidence for how the main groups of marine invertebrates evolved, and particularly for the pace and pattern of evolution in the Cambrian explosion. Besides including the earliest known representatives of some modern phyla, they have the great advantage of presenting a nearly continuous record of Early Cambrian organisms whose bodies include hard parts.