Under-the-Radar Human Evolution

Designer babies have been discussed as a possibility for decades.  With the recent advancement to genome editing technology referred to as “CRISPR”, the discussions about the ethics of have been amplified.  This is because CRISPR has reduced hurdles to human genome editing in terms of cost and technical ease.  Three days ago, the following video was posted to YouTube:

Who needs peer-reviewed publications when you have YouTube?

This unorthodox reveal of the existence of genetically modified humans was shocking to the world at large, yet predictions of rogue scientists “skipping over ethical concerns and going for it” have been floating around for years.  More than one TED Talk has addressed the ethical concerns of designer babies.  Here is one for our last Amazon Review assignment of the year.


The ethical dilemma of designer babies | Paul Knoepfler

For more thoughts on this subject, try out any of the following movies:


How CRISPR lets us edit our DNA | Jennifer Doudna

Genetic Engineering Will Change Everything Forever – CRISPR

Great Ape Father Figures

For Evolution

Show notes from this video on YouTube:

“At the Senkwekwe Center for mountain gorilla orphans in Congo, a handful of Virunga National Park rangers live around the clock with four juveniles whose parents were killed. The rangers see their families only every few weeks and are very close to their charges. Chief caretaker André Bauma along with his team have hand-raised the gorillas since they were first brought to the center. The first gorilla, Ndakasi, was found when she was just two months old, near the body of her murdered mother. Bauma cared for her like a human child—letting her sleep on his chest for warmth and bottle-feeding her to help build her strength. After that, three more orphaned gorillas joined “the family” at the center. Since no mountain gorilla orphan has ever been successfully returned to the wild, they will always depend on humans.”

Are these gorilla caretakers interacting appropriately with the gorillas?  Are they teaching the orphans how to be parents similar to wild gorillas?  Keep these questions in mind as you read about this new study that documented gorilla father behavior over a few decades.

Biology from an Engineering Perspective

For Evolution

Chapter 8 of The Tangled Bank discusses evolutionary adaptations that came about due to different types of mutation.  First, if genes are duplicated within a genome, the copies might come under the control of a new promoter.  This could change the rules about when and how much a gene is expressed.  Second, gene recruitment can occur if mutations lead to a different protein function.  The protein could acquire a second function while maintaining the first function or the old function could be lost and a new function takes its place as the purpose of that gene.

Together, these examples drive home the idea that gene expression control (example: promoter properties) and gene coding information (example: protein function) can be thought of as separate “parts”.  Synthetic biology is based on the idea that the parts could be mixed and matched to intentionally lead to a specified function.  Genetic engineers can build ever increasingly complex processes by connecting more parts together.  As an introduction to this, we will watch “Synthetic Biology: Programming Living Bacteria” by Christopher Voigt.

Rapid Evolution

For Introduction to Evolution

In chapter 6 of The Tangled Bank by Carl Zimmer, we learned that there is a simple equation to describe the rate of evolutionary change:

Rate of evolutionary change = “heritability of trait” x “strength of selection”

In the Rapid Evolution video, TREY the Explainer provides a couple of textbook examples.  The three stories covered in 20 minutes include finches in the Galapagos Islands, wall lizards, and stickleback fish.  These examples show rapid evolution (and even speciation) within a few decades time.

Washington Fish

Stickleback fish from Lake Washington in 1957 and 2006

Image credit: Unknown.  (Was used in Seattle Times article)

Dating Older Humans

For Introduction to Evolution – Chapter 3 Amazon Review

In chapter 2, we learned about a few important historical figures that contributed to the pre-Darwin field of evolution.  William Smith’s “map that changed the world” provided the first example of “biostratigraphy” where the relative ages of fossils are inferred from the layer of rock/deposits the fossil is found.  Now, in chapter 3, we spent some time discussing radiometric dating, a method based on monitoring radioactive decay.  (See the illustration of alpha and beta particle release during the decay of radioactive lead…that started out as radioactive thorium.)800px-Thorium_decay_chain_from_lead-212_to_lead-208.svg

YouTube is cluttered with anti-evolutionists attempts at undermining the validity of radiometric dating.  There is more than one (or two) way to determine the age of fossils, so first read “Everything Worth Knowing about…Scientific Dating Methods” by Gemma Tarlach and take brief notes on the various methods.

Next, dig into the “Fossil from Arabian Desert…” also by Gemma Tarlach to see an example of fossil dating using the uranium time series method.  Draw a timeline of events described in this article.  Then write a standard Amazon Review.

Image credit: Eugene Alvin Villar for the Philip Greenspun illustration project.  CC BY-SA4.0.

 

Eight Independent Lines of Evidence for Evolution

For Introduction to Evolution

We will be reading The Tangled Bank by Carl Zimmer this semester as we are introduced to evolution.  Chapter 1 of that book brings up the incredible case of whale evolution.  This video does too, so it’s a great complement to your upcoming reading assignment.  Moreover, this video highlights eight lines of evidence supporting the conclusion that whales evolved from land mammals.  The eight lines are:

  • Comparative anatomy
  • Embryology & development
  • Fossil record
  • DNA comparisons
  • Species distribution
  • Evolution observed
  • Predictive power of evolution
  • Nested hierarchies of traits

 

Nothing in Biology Makes Sense…

The creation vs. evolution debate can grow very tiresome.  We will avoid spinning our wheels on this never-ending, heated disagreement for most of the semester.  However, today’s the day we touch that lightning rod.  To mix things up from the typical “only evolution” or “only creation” camps of thought, we will read a highly-cited essay by Theodosius Dobzhansky.  (If you’re following along at home, you will likely need to search the internet for this PDF since it is behind a paywall.  The title is, “Nothing in Biology Makes Sense Except in the Light of Evolution.”)

This article is worth reading not only because it is famous, but also because the author is both an evolutionary biologist and a devout Orthodox Christian.  Similar to last week’s video, the author highlights the independent lines of evidence that support evolution.  Unlike last week, Dr. Dhobzhansky brings God into the equation.  Enjoy!

Contemplating Future Artificial and Natural Human Evolution

Chapter 14 Study Guide

Contemplate   

Be sure to incorporate concepts that you have learned in previous chapters in your answers. 

  1. Could you envision different populations of future humans as different species?  Why or why not? 
  2. How might our changing climate affect our evolution? 
  3. What domestic animal traits are acceptable to attempt to “fix” via genetic engineering?  Genetic diseases?  Muscle enhancement? Others?  
  4. What human traits are acceptable to attempt to “fix” via genetic engineering?  Genetic diseases?  Muscle enhancement? Others? 
  5. If humans form a colony on Mars, would you expect their evolutionary pace to change?  If so, how?