For many years, scientists believed that almost all animal lineages burst into being during the Cambrian era (just after the end
of the Precambrian super eon). However, there have been many recent findings of animal-like fossils and "trace fossils" (fossils of an animal-like organism's movement) from the late Precambrian. Which of the following best explains why it took so long to realize there was animal-like life in the Precambrian? A) Animals from the late Precambrian had soft bodies.
B) There were many hard-shelled animals in the Cambrian.
C) The global climate was such that there was poor fossilization in the Precambrian.
D) There were very few animals during this period.
The Precambrian represents the time period, right from the beginning of the earth to about 540 million years back. It is divided into 3 parts, namely the Hadean, the Archean and the Proterozoic. Throughout this geological time, vast changes have taken place on earth. The first life forms of about 3.8 billion years old, that existed on earth were the simple unicellular organisms, whose traces were only found at some particular places. These organisms were very small and are comprised of soft bodies, so they were affected by the earth's dynamic processes. The organisms in order to get fossilized must contain hard parts. Due to the presence of soft bodies, the organisms were not fossilized and so it took a long time to demarcate that the late Precambrian organisms were animal-like life.
<u>stonewort, and many green algae such as the Spirogyra.</u>
Explanation:
As it was believed that the land algae were believed to be evolved from the stonewort plant and the blue-green algae like the cyanobacteria and the spirogyra that colonized the lands some 500 mn years ago was a freshwater alga.
After which the first land plants occur about 470 million years ago, and they were in the form s of moss and liverworts of the vascular in origin.
Cohesion: When water molecules stick to one another through cohesion, they fill the column in the xylem and act as a huge single molecule of water (like water in a straw). Capillary action: Capillary action is the movement of a liquid across the surface of a solid caused by adhesion between the two.
