For this topic, you will do the topics from the attached list and construct two

Question

For this topic, you will do the topics from the attached list and construct two one-page concept sketches. Remember that a concept sketch consists of a sketch (or series of sketches), labels, and complete sentences written around the sketch describing the important processes or parts of the sketch. For this topic, select a life topic from the attached list and construct a concept sketch. Remember that a concept sketch consists of a sketch (or series of sketches), labels, and complete sentences written around the sketch describing the important processes or parts of the sketch. Attached list: First land animals: when they appeared, what types of creatures they were, and how they are represented in the fossil record.

NEED SKETCHor series of sketches AND LABELS AND DESCRIBING!!!!!!!!!!!!!!!!!or series of sketches

Explanation / Answer

ANSWER-

First land animal record between 620 and 550 million years ago (during the Vendian Period) relatively large, complex, soft-bodied multicellular animals appear in the fossil record for the first time. While found in several localities around the world, this particular group of animals is generally known as the Ediacaran fauna, after the site in Australia where they were first discovered.

The Ediacaran animals are puzzling in that there is little or no evidence of any skeletal hard parts i.e. they were soft-bodied organisms, and while some of them may have belonged to groups that survive today others don't seem to bear any relationship to animals we know. Although many of the Ediacaran organisms have been compared to modern-day jellyfish or worms, they have also been described as resembling a mattress, with tough outer walls around fluid-filled internal cavities - rather like a sponge.

As a group, Ediacaran animals had a flat, quilted appearance and many showed radial symmetry. They ranged in size form 1cm to >1m, and have been classified into three main groups on the basis of their shape: discoidal, frond-like, or ovate-elongate. The large variety of Ediacaran animals is significant, as it suggests there must have been a lengthy period of evolution prior to their first appearance in the fossil record.

The Ediacaran is the youngest period of three that make up the Neoproterozoic Era, which in turn is the youngest of three eras within the Proterozoic Eon. The Ediacaran is sandwiched between the older Cryogenian Period and the younger Cambrian Period.

Many paleontologists held little hope that fossils would ever be found in rocks so ancient as the Ediacaran. It is now known that rock layers may be deeply buried, twisted, folded and melted by geologic forces. It is easy to see that such changes to rock would destroy any fossils that might otherwise have been preserved. Older layers of rock, which have been around for a longer time, are more likely to have undergone such changes, and are thus less likely to preserve fossils. With no known fossils from the Ediacaran little more could be said, but in the late 1900s macroscopic fossils of soft-bodied animals, algae, and fossil bacteria were found in these older rocks in a few localities around the world. With the discovery of these earliest fossils came a surge of interest in the Ediacaran and the Proterozoic Era that continues today.

The Ediacara impressions were derived from soft-bodied organisms similar to modern-day jellyfish, lichen, soft corals, sea anemones, sea pens, annelid worms, and seaweed, as well as some organisms unlike any that are known today. They lived on or near the surface of coarse-grained sediments in the shallow continental shelf or on the deep continental slope of late Precambrian continental margins. Ediacara remains occur in rocks ranging in age from approximately 600 million to 541 million years old; the most-complex forms occur in the last 20 million years of this interval. The oldest radiometrically dated assemblage of Ediacaran organisms in the world, found in the Avalon Zone of Newfoundland, has an age of 565 million years.

source-http://waikato.ac.nz/, http://www.ucmp.berkeley.edu/index.php

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