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Lab 18. Evolution and Lab 19. Human Evolution Objectives  E…

Lab 18. Evolution and Lab 19. Human Evolution Objectives  Explain how fossils help establish the sequence in the evolution of life  Explain how scientists use fossils to establish that organisms are related by common descent  Explain how comparative anatomy provides evidence that humans are related to other vertebrates and other primates  Compare hominid skulls and hypothesize a possible evolutionary sequence  Vocabulary:  Evolution  Common descent  Fossil record  Geometric timescale  Radiometric dating  Homologous  Analogous  Embryology  Hominid  Introduction:  When Charles Darwin first proposed the idea of Descent with Modification, know commonly called evolution, he spent years and years comping vast amounts of data so that he could provide as much evidence as possible. In fact, he took so long that he was almost beaten to publishing by another scientist who had come to the same conclusion as Darwin. His name was Alfred Wallace, and he actually sent his manuscript to Darwin for review. Rather than race Wallace to publish, Darwin proposed that they publish simultaneously and hold conferences together. This way they ended up combining their evidence and strengthening their case; that natural selection was the cause of evolution.  This lab will cover a few of the evidence of evolution. Others you will cover in lecture.   Part 1: Evidence from the Fossil Record  Fossils provide solid evidence that organisms from the past are not the same as those found today. They also show the progression of evolution through the eons. In fact, scientists have found fossils dating back as far as 3.5 billion-years! These fossils are of ancient photosynthetic prokaryotes which is amazing as there are no hard surfaces in a single celled organism, which are the structures that are most commonly fossilized and survive over time.   After carefully collecting and analyzing fossils from all over the globe and from all types of organisms, scientists have been able to place them with across the geologic timescale – the history of the earth that is. Studying the mass extinctions of organisms and changes in fossil composition has also allowed scientists to conclude when major globe wide events have happened.   Geologic Timescale:  Divisions of the Timescale  Notice that the timescale divides Earth’s history into eons, eras, periods and then epochs. There are four eons with three having past and currently it being the Phanerozoic eon, all together spanning the largest amounts of time individually. The epochs spanning the shortest amount of time individually. Also notice that the periods of the Cenozoic era are divided into epochs, illustrating how more attention has been given to the evolution of primates and flowering plants than earlier organisms.  The geologic timescale is typically depicted with the oldest time periods at the bottom and more recent periods towards the top to reflect the natural process of rock formation and sediment deposition over time. This arrangement mirrors how layers of rock and sediment accumulate in the Earth’s crust, with newer materials being deposited on top of older ones. By presenting the timescale in this way, geologists can easily illustrate the chronological order of Earth’s history, showing how geological events and the development of life progressed from the earliest times (bottom) to the present day (top). 

Becoming Human Documentary Follow the link below to a websit…

Becoming Human Documentary Follow the link below to a website with an interactive documentary. Notice the top menu bar which has the listing of the areas: Prologue, Evidence, Anatomy, Lineages, and Culture. I have separated the questions based on the topic and episode.   Link to the documentary: https://becominghuman.org/documentary/