Fossils & Vestigial Structures - Science

Today this post is going more in-depth about Evolution and the evidence shown behind it, this is another given task which we had to work on independently. We were given a video explaining how Evolution was shown through fossils & body structures and how that made many hypotheses or/and theories about all the life forms that live within our planet which led to many discoveries we have so far uncovered. Below shows the provided video we had to learn from a little to answer a few questions which will be listed below. If you have not looked at my previous post, Natural Selection I'd recommend having a look at that first as there is a video included in that post that explains the myths and misconceptions about evolutions.

Evidence for Evolution

Reflection: The theory of evolution states that individuals within a species should provide of variation and those individuals which characteristics best suited to their environment are more likely to survive & reproduce.

What is a transitional fossil?

It is the fossilized remains of a lifeform that showing features from 2 distinct groups, it is a term called 'Misisng Link'. Transitional forms, organisms or fossils show the intermediate or midway states between an ancestral form and that of its descendant(offspring) can be referred to as a transitional fossils. It can indicate the types of animals and plants that existed in the past which is done by comparing fossilized body structures and fossilized tracks of movement, later on which they can peice together and tell how animals & plants have changed, developed and evolved overtime. 

By comparing fossils from different species, we can look for similarities in structure to try and work out which species are related to others. This visualizes how some species have evolved from others & gives us an understanding of how the evolutionary process works for example how many theories and evidence suggest we humans have evolved from apes.

Name 3 interesting discoveries we have made from fossil records?

• Around ten thousand(10,000) years ago, fossils of single celled organisms such as cyanobacteria from Australia have been found in rocks that are more than 3.5 billion years old.
• In 1998, scientist found a 317 million year old fossilized fish with a hand-like fin which suggested that it went through an evolution from being a sea dwelling creature to a land creature.
• Our lost common ancestor lived about 5-7 million years ago, during those times over 20 hominid species have been discovered.

What is a Vestigial Structure?

A vestigial structure or vestigial organ refers to an organ or a part of the body feature in a species which has lost the functional role or/and that has no longer have a purpose of use due to going through a evolutionary process, it is where the vestigial structure/organ had played a functional role which performed some important role at a point in the past, where at a time when it was useful for our ancestors for them to survive and adapt. Example: There are evidence and theories gathered that we humans once had a tail, our coccyx or tailbone were once our tails. The tail slowly shrunked, but the tailbones helped our ancestors with balance and mobility until we learned how to walk upright. Afterwards along the year the tailbone or coccyx served no purpose in human anymore and lost the functional role. 

Although a thing to keep in mind is that tracing the lineage of plant & animal species using fossil records is NOT exact science, due to lack of transitional fossils makes it harder leading to crucial gaps in the fossil record. But because the formation of fossils is a rare event, many transitional species have just not yet formed fosiils. Nevertheless with new fossils being unearth all the time we can anticipate at least some of these gaps to eventually be filled.