Direct evidence of evolution.pptx

Direct evidence of evolution
Evolution is a key unifying principle in biology. As Theodosius Dobzhansky once said, “Nothing in biology makes sense except in the light of evolution.”
Evolution is the change in the heritable characteristics of
biological populations over successive generations.
Charles Darwin on his journey around the earth
has found evidence of gradual changes(evolution).We can categorize the evidence into 4 main categories.
They are-
1. Biochemical
2. Fossil record
3. Comparative Anatomy
4. Observable events
We can divide these 4 categories into 2 sections. They are
1. Direct evidence
2. Indirect evidence

1. Raziya Nasrin Course Name: Fundamentals of Biological Science Direct evidence of evolution

2. Evolution Evolution is a key unifying principle in biology. As Theodosius Dobzhansky once said, “Nothing in biology makes sense except in the light of evolution.” Evolution is the change in the heritable characteristics of biological populations over successive generations. Charles Darwin on his journey around the earth has found evidence of gradual changes(evolution). He found many types of evidence.

3. Evidence of evolution We can categorize the evidence into 4 main categories. They are- 1. Biochemical 2. Fossil record 3. Comparative Anatomy 4. Observable events

4. We can divide these 4 categories into 2 sections. They are 1. Direct evidence 2. Indirect evidence. Direct evidence Fossil Record Biochemical Evidence of evolution Indirect evidence Comparative anatomy Observable events

5. Direct evidence The visible evidence which takes us back in time and shows organisms have changed. Example: Fossil record , Biochemical evidence.

6. What is fossil? Fossils are the remains or traces of ancient life that have been preserved by natural processes. Examples of fossil include shells, bones, stone imprints of animals or microbes, exoskeletons, objects preserved in amber, petrified wood, coal, hair, oil, and DNA remnants. The fossil record provides incomplete information about the history of life. Over 99% of all species that have lived on Earth have become extinct.

7. How fossils form? Dead organisms are buried by layers of sediment, which forms new rock. Most fossils are formed in sedimentary rock. The preserved remains may be later discovered and studied. The fossil record provides evidence about the history of life on Earth.

8. This is a picture of plant fossils was found in coal from the Minto area. It is 300 million years old (older than dinosaurs ) The oldest reliably classified fossils belonging to the genus Homo date back to a little over 2 million years ago.

9. Fossil Dating Relative dating allows paleontologists to estimate a fossil's age compared with that of other fossils. In relative dating, the age of a fossil is determined by comparing its placement with that of fossils in other layers of rock . Rock layers form in order by age the oldest on the bottom, with more recent layers on top . Stromatolites are the oldest known fossils, representing the beginning of life on Earth.

10. Carbon Dating Radiocarbon dating (also referred to as carbon dating or carbon-14 dating) is a method for determining the age of an object containing organic material by using the properties of radiocarbon, a radioactive isotope of carbon. The method was developed in the late 1940s at the University Of Chicago by Willard Libby.

11. What is Biochemical Evidence? Biochemical evidence of evolution is based on the fact that certain enzymes and chemical processes are found in the cells of all or nearly all life on Earth. Comparing DNA is the best evidence for evolution. Similar DNA sequences are the strongest evidence for evolution from a common ancestor. Biochemistry provides evidence of evolution in terms of modifications in various biological molecules, such as enzymes.

12. Although the biochemistry of organisms was not well known in Darwin’s time, modern biochemistry indicates there is a biochemical similarity in all living things. This comparison of biochemical processes with ancient species is called comparative biochemistry. For example, the same mechanisms for trapping and transforming energy and for building proteins from amino acids are nearly identical in almost all living systems. DNA and RNA are the mechanisms for inheritance and gene activity in all living organisms. The structure of the genetic code is almost identical in all living things. This uniformity in biochemical organization underlies the diversity of living things and points to evolutionary relationships

13. The Genetic code Triplets of DNA nitrogen base sequences that code for specific amino acids. The amino acid triplet is the same in almost all organisms.

14. Darwin’s explanation of evolution is called Natural Selection. Organisms don’t change to survive, they survive (or die!) because they change!

15. References https:// slideplayer.com /slide/267202/ https:// www.cliffsnotes.com /study-guides/biology/biology/principles-of-evolution/evidence-for-evolution Anon, Available at: https:// www.google.com / search?q = biochemical+direct+evidence&hl = en&sxsrf = AOaemvJqLgAilOOQz1PI-o6rvvaZMPaUTg:1640937543606&source = lnms&tbm = isch&sa = X&ved = 2ahUKEwjcjIrbyI31AhUySWwGHWxRDGcQ_AUoAXoECAEQAw&biw = 1366&bih = 625&dpr = 1#imgrc = nn30MwZZyWakcM&imgdii = deOkhyP_2YIqGM . Anon, Available at: https:// www.google.com / search?q = paleontology+direct+evidence&source = lmns&bih = 625&biw = 1366&hl = en&sa = X&ved = 2ahUKEwiv7b36po31AhXBNLcAHeRbCDMQ_AUoAHoECAEQAA . https:// en.wikipedia.org /wiki/Evolution