A bottleneck also occurs where breeders use popular sires.
For example a racehorse that is a great progenitor. He produces winners. Everyone uses him. He is found in line breeding, over and over in pedigrees. But then, the inbreeding /linebreeding genetic weaknesses are also magnified down through the pedigree, as well as the qualities that make a horse run fast. That’s why so many thoroughbreds are explosive nutcases if not racing.
A show winning poodle sire used a lot as a sire will lead to bottlenecks in the show poodle population.
Working police and military dogs- Belgian shepherds, The lines that produce the most active, bold, unstoppable, determined dogs are being very successfully condensed down to breed a litter of super working dogs, They will go to war or bring down the crook , kill and thrive on it. You can parachute them out of choppers and onto a live staging ground no worries. They land and are eager to get on with catch and kill.
But this is producing a bottle neck in a working line that’s going to bite us in the butt (pun intended) in a decade or so.
The lack of genetic diversity as a bottleneck was described in a major paper some years ago. Genes, in order to exist, have to have a previous source in an existing population. Over time, genes can mutate (good and bad)and that is a situation which can increase or decrease succeeding populations. Obviously, environment changes can also produce a “bottleneck”.
Personally, I am very concerned about critically endangered species. When violins are taken away from an orchestra, the symphony is damaged.
“then *we have nothing to fear” *in any scientific theory about how matter and energy evolve over time." occurs in the section “Pray the Creed, and mean it”
“Pray the Creed, and mean it” is something we should do. However, the Catholic Creed is not about basic Science of Human Evolution. It is the word “Evolution” in the article’s title that we should consider first.
The computer ate my original draft for this post. That is probably a good thing. :o
Every author is entitled to free speech. Thus, I cannot insist that Stacy Transancos explain the challenges of the Science of Human Evolution and how these will “attack” some basic doctrines like Original Sin and the ultimate full Divinity of Jesus Christ. (CCC 389, last sentence) Still, the quote “then *[FONT=“Arial”]we have nothing to fear” * is a demanding proposition which, in my personal opinion, has its own goal. [/FONT]
The question on my mind is – could “Pray the Creed” be a mistake in creation apologetics?
Granny, it’s crucial we get these definitions correct. The understanding, ramifications and management, or not, of a genetic bottle neck, means so much.
You described the bottleneck as a reduction in size of an existing population.
Do you understand the difference in a population of 10 blowflies with wide genetic diversity between them ,
And a population of 10 blowflies whose genetic profile results from severe inbreeding.
Genes will exist regardless of what’s going on in previous populations. It’s the variety we are interested in, for example, are you given a box full of caramel chocolates for granny day, or given a box full of mixed chocolate flavours.
I feel you have failed to acknowledge, or discuss the major point made in this coffee chat article. Let’s face it, it’s one woman’s 5 minutes of fame opinion, even if she is a chemist. And her point is quite good, although I dont think it should be using the Creed to support it.
This is her point
“”***If you are confident that God created … the person as well as all the diversity of flora and fauna, the elements as well as the angels, then it never, ever should concern a Christian if scientists propose how biological diversity might have evolved.
Jesus said that the truth will set you free (John 8:32), and that’s exactly what I’m talking about. The truth is that there is no absolute randomness or chance in a universe created and held in existence by God. And presto! The false dichotomy is gone.
By focusing on disproving evolution, Christians stir up a crisis of their own making. We should be evangelizing through science, showing others how the ubiquitous order and beauty in creation enriches faith and points beyond the physical realm.
After all, the creativity and rationality that inspires Mr. T and me to move things around and fix up our home—and inspires all our neighbors to form a community, citizens to form nations, and, yes, scientists to form theories—was granted because we are made in God’s image and likeness, co-creators. The flower beds may be my design whereas the woodland is not, but all creation, both natural and supernatural, is the handiwork of God.""***
So what, granny, is the author saying in those paragraphs?
What she is saying is correct. There are no seen problems. By the way, there have been a few times in my professional career when I acted as an investigative journalist in a restrictive area where real folders were kept in steel cabinets. I love to tell how I outsmarted two FBI agents headed my way.
My point is that one of the skills of a good journalist is the talent for finding missing information. Thus, if we are to look correctly at the Evolution article, we need to find out if any absolutely needed to understand Evolution information is missing. As an example, here is an interesting clue. “We have nothing to fear” and that continues to 'in any scientific theory about how matter and energy evolve over time." This automatically requires that one bring out Humani Generis. Here is the link. w2.vatican.va/content/pius-xii/en/encyclicals/documents/hf_p-xii_enc_12081950_humani-generis.html
Fortunately or unfortunately, I have a good idea what a lot of folk need to better understand basic evolution. Pope Pius XII used the term polygenisn. Scientists use the word polygenesis.
Twice I have tried to answer this post using the research paper “The Myth of Eve: Molecular Biology and Human Origins.” Francisco J. Ayala, 1995. I get to the section on “Population Bottlenecks” and I hit the wrong key because everything disappears.
My guess is that I initially learned about a bottleneck population from the research on the DRB1 human gene lineages in the above research paper. To me, this is a different arena from a population of 10 blowflies with wide genetic diversity between them. Still, it is genetics which forms the base of both. And we should not pit one against another.
First we should get to know the author Stacy. She tells us about herself.
"I am a chemist by training, and as a Catholic I frequently write about evolution, which garners a critical response from people who want to set me straight about the “Darwinian crisis.”
Comment. It is good for a Catholic to write about evolution. We need the education.
Question. What is the current Darwinian crisis?
Granny, I was gently attempting to point out to you that your definition of a population bottleneck was wrong.
This statement is wrong. Unsurprisingly it’s your Wikipedia link
"A population bottleneck or genetic bottleneck is a sharp reduction in the size of a population due to environmental events (such as earthquakes, floods, fires, disease, or droughts) or human activities (such as genocide). "
This is wrong
““is a sharp reduction in the size of a population””
In fact the term ‘population bottleneck’ is incomplete.
If any of my students gave me that answer in an exam or essay, they would get zero.
If any of my students referenced Wikipedia in any work, they would be relegated to rewriting with valid current texts
I am in your boat. Thank you friend, for your honest response.
It took me many days, weeks, to understand the depth of the article. Then I asked for advice.
What I hope to do is to start over and follow my original path with a few extra turns. I respect Dr. Trasancos and her desire to make evolution understandable. This is good. The basic problem is where the Science of Human Evolution intersects with a few fundamental doctrines. Many good Catholics are not totally aware what this intersection means. In fact, I bet there are lots of Catholics who do not know why I use the modern term Science of Human Evolution.
Please note that I did not make up my definition of a bottleneck. It is based on a paper by Francisco Ayala which was popular years ago. I do not claim expertise in this. Granny is not the sharpest knife in the drawer.
With that comment, I yield to the definition provided by you.
No doubt I misused the term population bottleneck, and I’m sorry to see that it has generated so much heat on this thread while I am inclined to think the concept is not crucial to a Catholic understanding of human evolution.
A brief thought which may help understand evolution science.
In the Catholic Church, there is a huge difference between the material world of evolution science and the spiritual world which eventually leads to the Beatific Vision. The Catholic Church does not declare doctrines based in the material world. Everyone has free speech when it comes to explaining the marvels of the material world.
What Catholics need to do is to learn which Catholic doctrines can intersect with the material world. For example. Human’s decomposing anatomy is part of the material world while Genesis 1: 27 is definitely part of the spiritual world. This combination places humans in the spiritual world. Practically speaking, the origin of the human species is defined by the spiritual world Catholic Church. Birds, buffalo, bacteria, bananas and busy beavers are part of the material world and we can suppose that evolution science helped them. This means that we cannot say that all evolution science is bad. At the same time, we have to lift the human species out of the material world in order to understand the magnificent human nature.
I hope this helps. At least boundaries are apparent.
In post 28, we learned that Dr. Trasancos likes to write about evolution. This is evident because she subsequently reflects that “a passerby would not conclude that our yard is the product of random chance. Mr. T and I used our God-given powers of intellect and will to decide how we wanted our place to look, and we worked our muscles sore to make it happen.” This is good. However, I wonder what God would do.
Nature and natural beauty can lead to a brief meditation. We could say that God decided how humans would look and especially what capabilities human nature would have. Genesis 1: 27. Like Stacey’s thought about her yard, we are not a product of random chance. Later she says: “I don’t see how anyone can look at a periodic table and doubt there is a designer.” Would we feel silly looking at our self in the mirror and then whispering that God is a great designer?
The simple point is that we did not come from random chance like many of the species we know today. Evolution’s random genetic chance needs a large mixed genetic polygenesis source. We came from a source of two already fully-complete humans. When we explore Catholicism, we learn that we come from an unique non-random source of two. This is why there are doubts about the end of the article, where there are the words “[FONT=“Arial”]we have nothing to fear …” If evolution is king with its large originating populations, what happens to our united uniqueness? [/FONT]
Note: random chance can be explained in different ways. If some bunnies turn white because of the surroundings (that may be an old tale about adaptation) there is the possibility that the solidarity of humankind is split in a variety of ways. Does that impact God’s call to all humans to come to Him in eternal joy? Maybe we need to fear how evolution actually works when there is a population creating another population.
There are only 3 ways around this issue that i can think of from a theological prospective.
We must believe and accept the idea that there were in fact a large group of humans walking around with no soul. Adam and Eve were the only humans with souls because God endowed them with souls. But then the question is what happened to the Homo-sapiens that had no soul?
The other option is to suggest that Adam and Eve is not a product of evolution but were created directly by God just like it says in genesis. But then how do we explain our genetic linage?
There was a large group of homo-sapiens that had souls but only Adam and Eve had children. But again what happened to the other humans?
Sorry Granny this is a tough one. Which is probably why Catholic Answers have not responded to you.