How Fast Is Evolution?
Sign in to YouTube
Sign in to YouTube
Sign in to YouTube
Uploaded on Mar 14, 2010
http://www.facebook.com/ScienceReason ... Facts of Evolution (Chapter 5): How Fast Is Evolution?
Please SUBSCRIBE to Science & Reason:
EVOLUTION IS REAL SCIENCE:
1. Does The Evidence Support Evolution?
2. Vitamin C And Common Ancestry
3. Are We Descended From Viruses?
4. Does The Fossil Record Support Evolution?
5. Where Are The Transitional Forms?
FACTS OF EVOLUTION:
2. Universal Common Descent
3. Good Design, Bad Design
4. Speciation And Extinction
5. How Fast Is Evolution?
6. What Can Embryos Tell Us About Evolution?
7. The Molecules Of Life
8. Molecular Evolution: Genes And Proteins
9. Retroviruses And Pseudogenes
Rates of Evolution
Evolutionary rates can be measured quantitatively for a character within a lineage, and we begin by seeing how this is conventionally done. We then look at a large compilation of over 500 such measurements and ask whether fossil evolutionary rates fit in with the theory of population genetics.
Punctuated equilibrium is an influential modern idea about evolutionary rates in fossils and we discuss the theory, how to test it, evidence for and against it, and its conceptual relation with the modern synthesis.
The rate of evolution is a measurement of the change in an evolutionary lineage over time.
The method for measuring the rate of evolution can be illustrated by work done by MacFadden on horse teeth: horse teeth are classic materials in the study of evolution.
The rate of evolution is measured as follows:
Suppose that a character has been measured at two times, t1 and t2 ; t1 and t2 are expressed as times before the present in millions of years.
The time interval between the two samples can be written as:Dt = t1 - t2,
which is 1 million years if t1 = 15.2 and t2 =14.2 The average value of the character is defined as x1 in the earlier sample and x2 in the later sample; we then take natural logarithms of x1 and x2 (the natural logarithm is the log to base e where e = 2.718, and it is symbolized by ln).
The evolutionary rate (r) then is
r = (ln(x2) - ln(x1)) / Dt
The rate of evolution is measured in 'darwins'.
Haldane defined a 'darwin' as a unit to measure evolutionary rates; one darwin is a change in the character by a factor of e in one million years.
The formula above for r gives the rate in darwins provided that the time interval is in millions of years.
Standard YouTube License
- 10:58 Special Investigation - Evolutionby NonStampCollector Featured 262,389
- 2:21:25 Creation / Evolution Debate 19 - Three on One! - Dr. Hovind vs 3 Embry-Riddle University Professorsby slaves4christ44,339 views
- 1:49:48 100 Reasons Why Evolution Is STUPID! - Kent Hovind Christian Creationistby Kerrigan Skelly132,569 views
- 1:46:56 Evolution: How We Know it Happened & Why it Matters (with Dr. Donald Prothero)by Skeptic Magazine71,103 views
- 2:34:31 Creation/Evolution Debate - Kent Hovind vs. UC-Berkeley Finally Hears the Truthby Kerrigan Skelly37,994 views
- 1:33:42 The God Delusionby ScientificUnity578,415 views
- 10:25 Evolution Of Modern Humansby Best0fScience115,145 views
- 10:28 Punctuated Equilibrium and Creationist Dishonestyby DonExodus225,026 views
- 8:55 9. Is Intelligent Design Viable?: William Lane Craig rebuttalby drcraigvideos4,820 views
- 9:42 Evolution: Where Are The Transitional Forms?by Best0fScience25,779 views
- 7:35 The Dark Matter Mystery: Most Of The Universe Is Missingby Best0fScience29,967 views
- 10:06 Einstein's Relativity: Basics And Impact In Our Everyday Lifeby Best0fScience199,390 views
- 6:46 Evolution Is Only A Theoryby FFreeThinker180,721 views
- 6:57 Facts Of Evolution: Universal Common Descentby Best0fScience47,071 views
- 3:44 What Can Embryos Tell Us About Evolution?by Best0fScience39,858 views
- 13:30 Evolutionists Get Owned By Creationists on BBC TV Showby MultiStanDaMan1,085,439 views
- 58:37 Revelation TV Interview with Richard Dawkins, amazingly idiotic Creationist questions!by Random Film...397,398 views
- 7:58 Facts Of Evolution: Good Design, Bad Designby Best0fScience52,084 views
- 57:48 Creation / Evolution debate on Michael Coren Showby wazooloo570,037 views
- 10:30 The Creationists' Nightmareby AuntieDiluvian277,668 views
- Loading more suggestions...