Information

Is there any genetic similarity that defy evolution theory?


For example,

say species A is common ancestor of B, and C. Species B is a common ancestor of D and E.

We would expect that there will be more genetic similarity between D and E than D and C. And those genetic similarity must exist in B.

In other word, we won't expect genetic similarity that don't "cross" the common ancestor or the evolutionary tree.

The exception is probably genetically engineered bacteria.

That being said, am I correct?

Some people say that we have similarity with pigs and chimps even though our common ancestors may be to far off. That won't happen right?

To summarize

I expect that evolutionary tree will form a well, tree. Genetic similarity would infect "nearby" trees and can't jump between trees without connectors, such as common ancestors.

Is that what we observe for ALL species?


You have an excellent answer from Remi.b already but I just wanted to add/emphasise this (because there is always more than one way of explaining something and IMO the site benefits from having many answers to the questions)…

The tree we construct does not necessarily accurately reflect what happened in evolution. If B & C evolved from A, and D & E came from B, we would create this tree if we measured using the correct indicator. But the methods we have are not perfect. The first evolutionary trees were based on morphological descriptions etc. and clearly some of the classifications were going to be wrong. These days we use molecular methods, which are probably more accurate but could also be wrong some times. For example if we based our phylogeny on one SNP variant we could have some idea about the phylogeny between a few species, but if we based it on millions of SNPs we would have a much better idea - as technology & models improve that is becoming more realistic. The key point here being there is a difference between the trees we can draw from evidence, and the real evolutionary tree.

If, for example, D evolved from B but was more genetically similar to C it could be due to convergent evolution (if the same mutations are selected for in C and D but neutrally or negatively in B). This is because, if there is a shared standing genetic variation at the point of speciation or the same mutations occur after speciation, and then C & D are imposed under similar selection and B is not, the allele favored in that environment will spread in C & D but not B (it may drift in B).

Imagine this with humans, where populations split off around the globe. Two populations spread from Africa (A) in to Southern Europe (SE) and Western Asia (WA). Population WA then derived two more populations - Central Asian (CA) and Eastern European (EE). If the Eastern European population developed a habit for drinking cow milk, and that information passed to the Southern Europeans, then selection would favor the ability to digest lactose in those two populations. If we then used the lactase persistence SNP (which had standing genetic variation at the time of divergence) to derive a phylogeny the populations SE and EE would appear related because the allele for lactase persistence is common, but in A WA & CA it would be rare (neutrally evolved). In this case the phylogeny we construct would be different to the true phylogenetic tree.

Basically if there is genetic variation at the point of divergence, or convergent selection, or any gene flow occurs after divergence it makes assessing the phylogeny more difficult and prone to error.


Your question seems rather confused to me, I don't quite understand it. Below I try to explain some stuff, I am not quite sure it would help you finding the answer to your question. Let me know if it helps you and how I can improve this answer.

While natural selection selects for a given allele (gene variant), mutations create new variation. And because of this process of mutation there is genetic pattern in species D that would cannot be found in species B (assuming that we have the DNA of species D). But what is similar between B and D were probably also present in their common ancestor B. The exceptions are molecular convergent evolution and horizontal gene transfer (natural of artificial).

Because of common ancestry…

  • Humans have similarities with pigs
    • Example: endothermic amniotes
  • Humans have similarities with a bug
    • Example: bilaterial symmetry
  • Humans have similarities with jellyfish
    • Example: Heterotrophy
  • Humans have similarities with an oak tree
    • Example: We have mitochondrias
  • Humans have similarites with any living things on earth!
    • Example: Genetic information is hold into a DNA/RNA molecule.

If you might observe that D is genetically speaking more similar to C than to E… This can be due to:

  • Horizontal gene transfer (artifical or natural)
  • The mutation rate (or ability to fix mutations) in one lineage might be greater than in another lineage.
    • For example, if lineage E underwent many mutations, they might be genetically speaking have accumulated many difference compare to D, way more than the number of difference that D has with C.
  • The phylogeny might be wrong
  • There might have had some convergent evolution.
    • Think about fishes which opsins in the eyes need to be adapted to the amount of light which depends on the turbidity of the water. After the three lineages splitted, the change of envirronment might have occured the sequenceAATGATCCTsuddenly became beneficial. Only two lineages had the chance to produce the right mutation. Or maybe lineage E live at low depth and therefore it doesn't need this mutation because there is enough light at low depth anyway.

Therefore, one should not expect a common ancestor to be the arithmetic mean (supposing it means something) of the current species. And one should not expect that two closely related species on the tree of life should necessarily be more genetically similar to each other than any of the two to a third species.

Note that the phylogeny is constructed mostly based on genetic data. Which makes that two closely related species (on our tree which is not necessary the absolute tree of life) are (almost) necessarily more genetically similar (it is kind of a definition then).


Theory of Evolution: Definition, Charles Darwin, Evidence & Examples

In 1831, an inexperienced 22-year-old British naturalist named Charles Darwin jumped on the HMS Beagle and sailed the world on a five-year scientific voyage that earned him a place in science and history.

Known today as the “father of evolution,” Darwin amassed compelling evidence supporting the theory of evolution by natural selection. Earlier scholars, including his grandfather Erasmus Darwin, were mocked for presenting such unorthodox ideas as transmutation of species.

Darwin is credited with being the first scientist to persuasively argue a unifying theory of how species evolve and continue to change.


The Institute for Creation Research

With the advent of modern biotechnology, researchers have been able to determine the actual sequence of the roughly three billion bases of DNA (A,T,C,G) that make up the human genome. They have sequenced the genomes of many other types of creatures as well. Scientists have tried to use this new DNA data to find similarities in the DNA sequences of creatures that are supposedly related through evolutionary descent, but do genetic similarities provide evidence for evolution?

DNA Supports Distinct Kinds

In the June 2009 Acts & Facts, an article was published by the author that showed how this approach has been used in an attempt to demonstrate an evolutionary relationship between humans and chimpanzees. 1 The article showed that scientists incorporate a large amount of bias in their analyses in order to manipulate the data to support evolution, when in fact the DNA data support the obvious and distinctive categorization of life that is commonly observed in the fossil record and in existing life forms.

In reality, there is a clear demarcation between each created kind (humans, chimps, mice, chickens, dogs, etc.), and there is no blending together or observed transition from one kind of animal to another. All created kinds exhibit a certain amount of genetic variability within their grouping while still maintaining specific genetic boundaries. In other words, one kind does not change into another, either in the fossil record or in observations of living organisms.

Similar DNA Sequences

While the genome of each created kind is unique, many animal kinds share some specific types of genes that are generally similar in DNA sequence. When comparing DNA sequences between animal taxa, evolutionary scientists often hand-select the genes that are commonly shared and more similar (conserved), while giving less attention to categories of DNA sequence that are dissimilar. One result of this approach is that comparing the more conserved sequences allows the scientists to include more animal taxa in their analysis, giving a broader data set so they can propose a larger evolutionary tree.

Although these types of genes can be easily aligned and compared, the overall approach is biased towards evolution. It also avoids the majority of genes and sequences that would give a better understanding of DNA similarity concepts.

Tumor Suppressor Genes

As an example, there is a group of genes that not only have been used in evolutionary studies, but also have a significant impact on human health: the tumor suppressor genes. Aberrations within tumor suppressor genes can lead to cancer, thus it is important that their sequences remain unaltered. These genes tend to be very similar across many types of animals, making them ideal for comparative purposes. The close similarities of these genes between many animal taxa have led to their use by scientists in an attempt to prove evolution or common descent. 2 What is really going on with these types of similar genes and how can they be interpreted within a special creation model as opposed to a naturalistic framework?

In very general terms, tumor suppressor genes are key genomic features (blocks of genetic code) that help regulate the growth and division of animal cells. When these genes are functioning properly, they code for proteins that can prevent or inhibit the out-of-control cell proliferation that forms the basis for the growth of tumors. When tumor suppressor genes are inactivated due to a DNA mutation, cell growth and division are no longer kept in check, resulting in cancer.

There are three main types of tumor suppressor genes. One type signals cells to slow down and stop dividing. Another type of tumor suppressor gene produces a protein that is responsible for checking and fixing damage in DNA that can happen when cells divide and proliferate. A third is responsible for telling cells when to die in a process called apoptosis. Cell growth, proliferation, and controlled cell death are essential to the development and maintenance of all animal systems.

For example, human hands develop from an initial fan-shaped structure, where apoptosis (programmed cell death) removes cells between fingers, and cell growth and division build up the fingers. How these genes are regulated will vary with the organism. However, because the basic aspects of the cell cycle are generally similar in many animals, one would actually expect a high level of DNA sequence conservation (similarity) between the coding parts of the genes as well as the proteins they produce.

The Ultimate Genetic Programmer

Generally, the more common a cellular process is between organisms, the more similar its various components will be. Does this indicate random chance evolutionary processes, or could it be an example of the Creator&rsquos wise and efficient use and re-use of genetic code in different creatures to accomplish a common and basic cellular function?

Consider the computer world. Ask seasoned computer programmers how often they completely re-write long, complicated blocks of code when they already have what they need somewhere on file. When a long piece of previously-written code is needed and available, programmers will tailor it to fit in its new context, but they will usually not completely re-write it.

Of course, God is the ultimate programmer, and the genetic code He developed will produce the best possible protein needed for the system in which it works. If another organism has a similar physiology, one can expect many of the same genes to be present in its genome. There are a finite number of ways to accomplish the same task in cells. Thus, the genes that are used to accomplish that task will usually be quite similar, with minor key variations. These slight differences exist because the Creator has optimized the genes for that particular kind of creature and its biochemistry.

What the data really show is that high levels of efficiency and utility in genetic information seem to be a recurring theme in the study of genomes. In fact, with the limited number of genes in the human genome (about 25,000), over one million different protein variants are derived. 3 Although not the topic of this article, a single animal gene can code for a wide variety of different proteins through a variety of complicated regulatory mechanisms. When scientists discovered this phenomenon, it totally negated the one-gene/one-protein mentality that originally existed when DNA sequence first began to be studied. That is pretty efficient code usage, which has never been equaled by even the most complex computer programs devised by man.

Genetic Regulatory Elements

While evolutionists have focused on genes that code for proteins, work is just beginning on an equally essential and complicated class of DNA sequence called regulatory elements. These are DNA sequences that do not code for protein but are involved in the regulation of genes. While efficient code usage and re-usage is common among many genomes, what is important is not just the protein the gene generates, but how much, how often, how fast, and when and where in the body it is produced. This is where the gene regulatory process begins to get really complicated. These regulatory differences play a key role in defining what makes a certain kind of organism unique.

After the human genome sequence was obtained to a completion level satisfactory to the scientific community, a separate but heavily-funded and related effort was initiated called the ENCODE (ENCyclopedia of DNA Elements) project. 4 This involves ongoing research to determine the identity and characteristics of the regulatory elements in the human genome. At present, ENCODE has barely scratched the surface, but the results have revolutionized the concept of genetics by showing whole new levels of complexity and efficiency of code and gene activation.

The genetic picture that is beginning to emerge is one of incredible networked and regulatory complexity combined with an extremely high level of efficiency in code usage--certainly nothing that could have evolved on its own through chance random evolutionary processes. As is easily seen, trying to use common genes related to common processes as proof of evolution quickly falls apart in light of the bigger genomic picture. In fact, it really speaks of smart coding by the ultimate bio-systems programmer--God Himself.

  1. Tomkins, J. 2009. Human-Chimp Similarities: Common Ancestry or Flawed Research?Acts & Facts. 38 (6): 12-13.
  2. Jensen, L. J. et al. 2006. Co-evolution of transcriptional and post-translational cell-cycle regulation. Nature. 443 (7111): 594-597. . Posted on expasy.ch July 2007, hosted by the Swiss Institute of Bioinformatics. . Posted on the National Human Genome Research Institute website at genome.gov.

* Dr. Tomkins is Research Associate at the Institute for Creation Research.

Cite this article: Tomkins, J. 2009. Common DNA Sequences: Evidence of Evolution or Efficient Design? Acts & Facts. 38 (8): 12-13.


Creationists and Evolutionists Agree . . . Apes and Humans Share a Lot

Evolutionists love the great apes. They point to them as our “closest living ancestor” because of all their similarities with us.

We like them too, and we agree to a part of their description. The great apes are “close” in the sense that they do share quite a few traits with good ol’ Homo sapiens. They have hands with five fingers, including an opposable thumb. Their basic body layout comes pretty close to ours. Their brains have the capacity to learn simple communication skills through sign language or other nonverbal methods. Even their DNA shares many parallels to the DNA in our cells.

So, yes, the similarities are interesting—but so are the differences. Really, chimps, gorillas, et al. show the handiwork of a handy Maker. But that creativity comes through precisely because of how different they are from us. They weren’t made to walk on two legs—but they can knuckle-walk and swing through trees with beautiful grace. Their five fingers would look silly attached to our hands, but they’re exactly what you’d want for hanging around on limbs. Those brains wouldn’t get them into Yale, but they do a bang-up job computing how to dig up termites. And that DNA gives them the characteristics they need to thrive in their special environments, but it doesn’t come close to what God has enabled humans to do, the only creatures made in His image.

Why are the apes so similar to us? That’s a great question. Do you remember how I said we don’t have all the answers? Well, here’s a prime example. We have some ideas, but we don’t really know for certain all His purposes for the similarities. (All creatures are similar to us at some level, which makes it easier for us to live with them and oversee them as God ’s stewards.) Perhaps they remind us that physical qualities aren’t what make us truly unique and most like the Creator.

Whatever the case, apes do have similarities to humans. Anyone can see that. But the differences—ah, the differences—that’s what makes us able to praise our wise God with beautiful songs, while gorillas only grunt.


What is the genetic evidence for human evolution?

In the last couple of decades, our understanding of genetics has grown dramatically, providing overwhelming evidence that humans share common ancestors with all life on earth. Here are some of the main types of genetic evidence for common ancestry.

1. Genetic Diversity. Human children inherit 3 billion base pairs of DNA from each parent, but they are not an exact duplicate. The rate of change has been measured precisely to an average of 70 bases (out of our 6 billion total) per generation. So as we go back on the family tree, there are more and more genetic differences between us and our ancestors. For example, there would be about 140 differences between your DNA and that of your four grandparents, and 210 differences between you and your eight great-grandparents, and so on. That enables us to make a prediction from the amount of genetic diversity between two species about the time since their common ancestor population lived. Using non-genetic evidence, the common ancestor between humans and chimpanzees was estimated to have lived about 6 million years ago. The calculation from genetic differences gives a figure remarkably close to the estimated value.

2. Genetic “scars”. Just as scars stay on our bodies as reminders of past events, the DNA code contains “scars” and these are passed on from generation to generation. DNA scars result from the deletion or insertion of a block of bases (not just single base changes as in the previous section). Because we have a lot of these (hundreds of thousands) and they can be precisely located, they serve as a historical record of species. If we have the same scar as chimpanzees and orangutans, then the deletion or insertion must have occurred before these species diverged into separate populations. If we and chimpanzees have a certain scar but orangutans do not, we can conclude the deletion or insertion must have occurred after the common ancestor of chimps and humans separated from our common ancestor with orangutans. In this way we can create a detailed family tree of common ancestors.

3. Genetic synonyms. In a certain context, the words “round” and “circular” mean the same thing to an English speaker—they are synonyms. So too, there are “synonyms” in the genetic code—different sequences of DNA bases that mean the same thing to cells (that is, they cause the production of the same proteins). Mutations in the genetic code are often harmful, resulting in an organism not being able to successfully reproduce. But if the mutation results in a “synonym”, the organism would function the same and continue passing on its genes. Because of this we would expect the synonymous changes to be passed on much more effectively than non-synonymous changes. That is exactly what we find among the DNA of humans and chimpanzees: there are many more synonymous differences between the two species than non-synonymous ones. This is exactly what we would expect if the two species had a common ancestor, and so it provides further evidence that humans and chimpanzees were created through common descent from a single ancestral species.

The more research that is done on DNA, the more evidence we find that all life is related.

Last updated on:March 11, 2019

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Evolution? Impossible!

We’re sure you’ve heard this claim before, probably hundreds of times: “Science has proven evolution is fact.” It’s like a strange Darwinian chant that emanates from atheist blogs and secular universities. Too bad (for them) it’s not true.

In fact, refuting evolution doesn’t require complicated equations or lab experiments—though those do the job, too. Just remember the two fundamental flaws we can use to show evolution to be, well, not even scientifically viable.

Where’d You Get Your Information, Bub?

Everything that makes up your body requires genetic information. You’ve got hands and feet because your genes code for it. The same is true for any creature—dogs, camels, you name it.

The genetic information in humans varies from the information in animals, plants, and so on. Seems obvious, so why point it out? Because for animal kind A to somehow “presto-change-o” into animal kind B, the information’s got to change. A fish doesn’t just morph into an amphibian without something changing in the genes. It would have to gain some new information.

Here’s the clincher: when we use operational science—the kind involving observable, repeatable, testable results—we have never observed, repeated, or been able to test animal kind A turning into animal kind B—at all. Sure, there’s some genetic “do-si-do” going on through mutations and gene drift, but there’s no way fish are going to sprout hair and opposable thumbs. Just in case you think by “no way” we mean there’s still a chance, there’s not—none, zilch, nada, not going to happen. What if we add billions of years and cool artistic renderings? Still no.

Refute evolution in less than three minutes with this exciting mini-video from Check This Out! (a DVD or download featuring six warp-speed videos sure to spice up your teaching). Share everywhere.

Original Recipe

That first point is devastating enough. But here’s how evolution gets buried even more.

You’ve probably heard news accounts about how life could have started on earth “gazillions” of years ago in volcanoes, slush pools, crystals, rocks, you name it. Maybe you’ve heard something about “artificial” life or test-tube life or rotten-food-in-the-refrigerator life (okay, maybe not the last one).

Those are interesting speculations, but they overlook one important rule in biology: life doesn’t, cannot, and will never come from non-life. Life comes from life. Always. That’s the law—the Law of Biogenesis, to be exact.

All these failed experiments, like the Miller-Urey experiment, really show us just how much intelligence is required for life to begin in the first place. (That is, way smarter than us.)

And Yet We’re Here

So, if evolution can’t explain how humans came to be (or any other living thing, for that matter), what can? The Bible. Yep, God’s Word.

The Bible provides an eyewitness account of how the universe and all life came to be. There’s no speculation or strange interpretation needed. You can just read how God created everything in six days a few thousand years ago. Simple. Factual.

Pick it up, dust it off if you need, and read it. There’s even some good news in there for you.


Well-Adapted Underwater Animals that Defy Evolution

A wide variety of organisms spend all or part of their time under the surface of water, having just the equipment they need to thrive.

Masters of the Sea: Jellyfish

A new book by Juli Berwald talks about Spineless organisms: namely jellyfish. In an interview in National Geographic, she waxes eloquent about these highly adapted swimmers:

In terms of a muse to write about, they live on this line that is both angelic and demonic and nothing about them is clear-cut. They are absolutely gorgeous to look at and, you’re right, their bioluminescence is astonishing!

But their sting is vicious! They may not just ruin your time at the beach. Some are actually deadly. The box jelly, the very toxic one that lives in the Pacific Ocean, can kill a man in three minutes and contains enough sting for 60 men.

Speaking of that bioluminescence, a protein from jellyfish named Green Fluorescent Protein (GFP) has “revolutionized biotechnology” by allowing scientists to track reactions of individual proteins in cells embedded with the gene. Berwald talks about the incredible variety in jellyfish (attributing it all to evolution), and shares another astonishing fact about their stinging cells:

The fact that they’ve been around so long says that they’ve come up with a morphology, body structure, and adaptation to survive, hunt, and avoid being eaten, which is supremely elegant. In my opinion, it all comes down to the speed and force of their stinging cells, which are a masterful piece of biological evolution that explode with a force five million times the acceleration due to gravity.

And yet two facts argue against evolution: (1) jellyfish appear abruptly in the Cambrian Explosion (Evolution News), and (2) the stinging cells are irreducibly complex (5/08/06), unreachable by natural selection. Despite their vicious power, they don’t harm some organisms that eat jellyfish, such as whales, molas, albatross, penguins and sea turtles. Even humans make “jellyfish salad” (popular in Asia, Berwald says). Sea slugs can even ingest the nematocysts without triggering them, and exude them onto their backs for added protection. Also, if jellyfish are products of blind chance, why are humans rushing to imitate them? Berwald talks about “robojelly,” a robot that mimics JPL (jellyfish propulsion lab).

Update 12/15/17: Phillip Lamb at The Conversation has posted a pictorial essay of praise for jellyfish, saying they have “superpowers” and don’t deserve their bad reputation. They are masters at survival, he says—”among the most abundant organisms in the sea.” He speaks of their superpowers, like a moon jelly that can lay 400,000 young at a time, and their bioluminescence, and even their symbioses with photosynthetic algae, “which act like their own personal solar panels and let them obtain energy straight from the sun.” Jellyfish have been a boon for mankind, he argues. Three embedded videos tell more. Watch the mesmerizing light shows of ctenophores (comb jellies) in the first video. How did they get these abilities? Unfortunately, he chalks up these superpowers to evolution, but states it in this paradoxical form: “Many jellies have evolved unique abilities, some of which seem almost supernatural.” And how, exactly, do these facts square with Darwinism? “Gelatinous bodies have evolved independently three times and have existed, largely unchanged, for at least 500m years, surviving all five major extinction events in the Earth’s past that wiped out 99% of all life.”

Hundreds of Reflecting Eyes in a Shellfish

The scallop, whose shape Shell Oil uses for its logo, has an amazing secret: some 200 tiny eyes that give it a view of its surroundings. Evolution News talks about the design implications of this recent discovery about a “simple” mollusk (see Phys.org). The 200 poppyseed-sized eyes around the mantle of the scallop use biological mirrors made of square guanine crystals, giving it the properties of a segmented Newtonian telescope mirror (see embedded video in the Evolution News post). The precise shape of the concave mirror allows double reflection of the incident rays onto two stacked retinas, allowing for both escape signaling and wide-angle vision.

Precision Glass Manufacturing in a Brittlestar

An unrelated marine animal, the brittlestar (phylum Echinodermata) also has eyes all over its body, as we reported way back in 2001 (8/23/01). Its “near-perfect” lenses are also the envy of bioengineers. Another design feature of brittlestars was reported recently by Science Daily: its ability to make super-strong glass from its surroundings.

Nature inspires innovation. An international team lead by researchers at Technion — Israel Institute of Technology, together with ESRF -the European Synchrotron, Grenoble, France- scientists, have discovered how a brittle star can create material like tempered glass underwater. The findings are published in Science and may open new bio-inspired routes for toughening brittle ceramics in various applications that span from optical lenses to automotive turbochargers and even biomaterial implants….

Nature exhibits tremendous creativity in improving the organism’s abilities in various contexts such as strength, sensing, and self-defense. Here, too, in the process of creating hardy and precise transparent lenses, we see tremendous efficiency in the use of existing raw materials under conditions in the natural environment.

The focal lenses of these eyes covering its body are described as “powerful and accurate.” Echinoderms also appear abruptly in the Cambrian fossil record. Speaking of eyes dating from the Cambrian Explosion, look at the amazing modern-looking eye of a trilobite reported by the University of Edinburgh. This species of shallow-water arthropod dates from the earliest of all known trilobites, yet its eyes contained the basic features of modern bees and dragonflies, the paper in PNAS says. Did trilobites with elaborate eyes just pop into existence? (Read about the Popeye Theory of Evolution in our 5/31/05 commentary.)

Great White (Illustra Media)

Airplanes and submarines both move through fluid. Air is just a much less viscous fluid than water. Whether applying principles of aerodynamics or hydrodynamics, animals need dynamics to move through a fluid medium. An article in Science Daily describes sharks having “aircraft-like attributes” to move through the water. Some grow large livers to give them properties of a dirigible or blimp. Others glide like fighter jets with fixed-wing design. Researchers at multiple universities studied sharks, finding that “these top predators mirror the aerodynamics of either zeppelins or fixed-wing high speed aircraft, depending on whether they evolved to cruise through the deep ocean or motor through shallow waters.” No evidence for evolution was provided. The observations show intelligent design, but the authors confabulated with Jargonwocky to conjure up visions of evillusion according to the Stuff Happens Law (terms explained in the Darwin Dictionary).

Sea Lions with Functional Whiskers and Exceptional Skills

Here’s a mammal swimmer displaying several wondrous adaptations. Robyn Grant at The Conversation writes, “Sea lions have unique whiskers that help them catch even the fastest fish.” With “superb sensing” using their whiskers, which are the longest of any mammal, they can detect the size, shape and texture of a surface just by swiping a whisker over it. They have communication with their companions using a varieties of grunts, and even have cognitive abilities. Along with parrots, they are one of few animals that can bob their heads to a musical beat. Sea lions delight many an audience with their tricks and incredible sense of balance (can you balance a beach ball on your nose?). And with streamlined bodies, they are also superb swimmers.

This streamlining means the sea lions are able to move quickly and efficiently through the water. Front flippers are used to push themselves along, while back flippers are used for steering. They’re able to chase fish at speeds of around 25mph but are flexible enough to quickly change direction.

Deepest Fish in the Deepest Ocean

Marine biologists at the University of Washington have found what they believe is the deepest fish in the ocean: a strange-looking fish called the Mariana snailfish. In its gut they found a crustacean it had just eaten. The Mariana Trench where it was found is 8,000 meters (26,200 feet) deep. “Little is known about how these fish can live under intense water pressure the pressure at those depths is similar to an elephant standing on your thumb,” the authors say. “They don’t look very robust or strong for living in such an extreme environment, but they are extremely successful.

A Fly With a Diving Helmet

Even humorist Mark Twain noticed this next underwater animal. In Mono Lake, a salty lake in the foothills of the eastern Sierra Nevada in California, brine flies breed by the millions and are relished by seagulls. Twain noticed something interesting about these flies:

You can hold them under water as long as you please—they do not mind it—they are only proud of it. When you let them go, they pop up to the surface as dry as a patent office report, and walk off as unconcernedly as if they had been educated especially with a view to affording instructive entertainment to man in that particular way.

A new paper in PNAS by Michael Dickinson, the Caltech expert in insect flight whose story on the “fruit fly in the flight simulator” was one of the most”amazing” entries in Creation-Evolution Headlines 14 years ago this month (12/08/03), visited the lake with his lead author, Floris van Breugel, to study these unusual flies. How are they able to live underwater? The partners found out that they have “superhydrophobic” bristles that capture air bubbles effectively. “Mono Lake’s alkali flies are a compelling example of how the evolution of picoscale physical and chemical changes can allow an animal to occupy an entirely new ecological niche,” they say, without focusing much attention on evolution. In this case of microevolution, there is a pathway for adaptation, because it involved slight chemical modifications to already-existing chitin proteins.

Extinct Reptile Swimmers with Modern Ears

We’ve discussed underwater animals from half a dozen different phyla. How about an extinct reptile? Researchers at Oxford were surprised to find that sauropterygians (lizard-wings), an extinct group of “fully aquatic ‘underwater flyers’,” possessed mammal-like inner ears. Like sharks mentioned above, marine reptiles including the better-known plesiosaurs “flew” through the water with powerful flippers. Of interest this time were the inner ear bones, which have “similar inner ear proportions to those of some modern day aquatic reptiles and mammals.” We learn from the article on Phys.org that these extinct “sea monsters” not only “flew” like sea turtles but had inner ears like mammals—two similarities despite being unrelated. The authors call on their familiar ad hoc Darwinian rescue device, saying, “These interesting results are the product of convergent evolution, the process in which completely unrelated organisms evolve similar solutions to the same evolutionary hurdles.” The author finds this rescue device useful. The article also points to convergences in shape between pliosauromorphs and whales.

We hope you have enjoyed considering a few examples of the wonders of marine biology. Do any of these animals show half-baked adaptations? Such designs are far beyond the capabilities of blind chance processes, let alone “convergent evolution.” For more examples of underwater design, remember the Illustra Film Living Waters: Intelligent Design in the Oceans of the Earth. See the trailer on our Recommended Resources page. You can get them in quantity as Christmas gifts now in a 50-for-75-dollar sale at RPI. It gets better if you get all the same title, you can get 50 for $50.

Incidentally, the author has met Floris van Breugel (see Mono Lake story above) and knows him to be an outstanding photographer as well as a scientist. It’s good to see him working with Michael Dickinson, a very perceptive and creative researcher who really knows how to communicate wonder and awe at the design of insect flight.


Darwin and DNA: How genetics spurred the evolution of a theory

Our understanding of evolution today stems from the combination of two very different ideas. One came from a monk who studied pea plants in a Moravian monastery in the 1850s. The other came from a Victorian gentleman who spent five years as a naturalist on a voyage around the world, 20 years previously.

Although Gregor Mendel and Charles Darwin were alive at the same time, they never met and Darwin wasn’t aware of Mendel’s work. With hindsight, the union of the two men’s work seems like a marriage made in heaven (or hell, if you’re a creationist). In fact, for many years, it wasn’t obvious that Mendel’s studies of heredity had any relevance to Darwin’s theory of evolution by natural selection. It would take nearly 60 years for this jigsaw to be pieced together and give rise to the “modern synthesis” of evolution, which framed Darwin’s idea in terms of genetics.

How exactly did this new understanding arise? And why did it take so long?

The explanation starts with natural selection itself. According to this, only the fittest – the best adapted to the local environment – survive and breed, and in this way the population as a whole gradually transforms. The idea of evolution was already accepted by many biologists in the mid-19th century, but there was considerable opposition to the notion that it happened by means of natural selection.

The plausibility of this mechanism rests on the assumption that beneficial characteristics are passed more or less intact from one generation to the next. But it was not clear how this might happen.

To explain heredity, Darwin proposed a hypothesis &hellip

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THE FUTURE IS BRIGHT!

The examples that we have outlined here show the value of the ongoing interaction between genetics and the study of evolution. From being a major headache for early supporters of evolution, genetics paved the way for models of evolution based on the known properties of inheritance, so that the constraints experienced by genes and genomes in evolution were correctly incorporated into quantitative models, and new possibilities, unknown to Darwin, were discovered.

Evolutionary genetics is inherently interdisciplinary, fruitfully combining models (often mathematical and often stochastic, given the nature of genetics) with empirical data. This intellectual tradition, now ∼100 years old, deserves celebration along with Darwin's anniversaries. We hope that we have shown that evolution is more central to modern biological research than ever before and that this productive collaboration with genetics can be predicted to yield many further pure and applied scientific riches in the next hundred years. For this to happen, the need for a broad-enough education must be met. Biologists and doctors will need to understand genetics, and even some population genetics concepts, at least enough to collaborate with people with expertise in relevant quantitative methods. Mathematical ideas need to be demystified, as far as possible, so that biologists using phylogenetic and genetic marker or diversity analyses know what lies behind the computer programs that they use, an understanding without which the numbers that come out may lead to wrong conclusions. We need to regain a respect for the usefulness of statistics throughout biology and use it to test our ideas, as Darwin started to do. The same applies to theoretical modeling directed toward testable hypotheses, of which the idea of natural selection is still an excellent example, even though it has been extended to a far wider realm of biology than Darwin initially proposed and has given us many valuable tools at the interface between genetics and evolution. Darwin himself was interested in the functioning of organisms, not just in their morphology and relationships and the history of life, and he would surely have been delighted to see where his ideas have so far led us and how they have continued to be central within biology. In Dobzhansky's famous words:

Nothing in biology makes sense except in the light of evolution (D obzhansky 1973).


Race Is Real, But It’s Not Genetic

For over 300 years, socially defined notions of “race” have shaped human lives around the globe—but the category has no biological foundation.

P lease note that this article includes an image of human remains.

A friend of mine with Central American, Southern European, and West African ancestry is lactose intolerant. Drinking milk products upsets her stomach, and so she avoids them. About a decade ago, because of her low dairy intake, she feared that she might not be getting enough calcium, so she asked her doctor for a bone density test. He responded that she didn’t need one because “blacks do not get osteoporosis.”

M y friend is not alone. The view that black people don’t need a bone density test is a longstanding and common myth. A 2006 study in North Carolina found that out of 531 African American and Euro-American women screened for bone mineral density, only 15 percent were African American women—despite the fact that African American women made up almost half of that clinical population. A health fair in Albany, New York, in 2000, turned into a ruckus when black women were refused free osteoporosis screening. The situation hasn’t changed much in more recent years.

M eanwhile, FRAX, a widely used calculator that estimates one’s risk of osteoporotic fractures, is based on bone density combined with age, sex, and, yes, “race.” Race, even though it is never defined or demarcated, is baked into the fracture risk algorithms.

L et’s break down the problem.

F irst, presumably based on appearances, doctors placed my friend and others into a socially defined race box called “black,” which is a tenuous way to classify anyone.

R ace is a highly flexible way in which societies lump people into groups based on appearance that is assumed to be indicative of deeper biological or cultural connections. As a cultural category, the definitions and descriptions of races vary. “Color” lines based on skin tone can shift, which makes sense, but the categories are problematic for making any sort of scientific pronouncements.

S econd, these medical professionals assumed that there was a firm genetic basis behind this racial classification, which there isn’t.

T hird, they assumed that this purported racially defined genetic difference would protect these women from osteoporosis and fractures.

The view that black people don’t need a bone density test is a longstanding and common myth.

Some studies suggest that African American women—meaning women whose ancestry ties back to Africa—may indeed reach greater bone density than other women, which could be protective against osteoporosis. But that does not mean “being black”—that is, possessing an outward appearance that is socially defined as “black”—prevents someone from getting osteoporosis or bone fractures. Indeed, this same research also reports that African American women are more likely to die after a hip fracture. The link between osteoporosis risk and certain racial populations may be due to lived differences such as nutrition and activity levels, both of which affect bone density.

B ut more important: Geographic ancestry is not the same thing as race. African ancestry, for instance, does not tidily map onto being “black” (or vice versa). In fact, a 2016 study found wide variation in osteoporosis risk among women living in different regions within Africa. Their genetic risks have nothing to do with their socially defined race.

W hen medical professionals or researchers look for a genetic correlate to “race,” they are falling into a trap: They assume that geographic ancestry, which does indeed matter to genetics, can be conflated with race, which does not. Sure, different human populations living in distinct places may statistically have different genetic traits—such as sickle cell trait (discussed below)—but such variation is about local populations (people in a specific region), not race.

(RE)THINK HUMAN

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L ike a fish in water, we’ve all been engulfed by “the smog” of thinking that “race” is biologically real. Thus, it is easy to incorrectly conclude that “racial” differences in health, wealth, and all manner of other outcomes are the inescapable result of genetic differences.

T he reality is that socially defined racial groups in the U.S. and most everywhere else do differ in outcomes. But that’s not due to genes. Rather, it is due to systemic differences in lived experience and institutional racism.

C ommunities of color in the United States, for example, often have reduced access to medical care, well-balanced diets, and healthy environments. They are often treated more harshly in their interactions with law enforcement and the legal system. Studies show that they experience greater social stress, including endemic racism, that adversely affects all aspects of health. For example, babies born to African American women are more than twice as likely to die in their first year than babies born to non-Hispanic Euro-American women.

Systemic racism leads to different health outcomes for various populations. The infant mortality rate, for example, for African American infants is double that for European Americans. Kelly Lacy/Pexels

A s a professor of biological anthropology, I teach and advise college undergraduates. While my students are aware of inequalities in the life experiences of different socially delineated racial groups, most of them also think that biological “races” are real things. Indeed, more than half of Americans still believe that their racial identity is “determined by information contained in their DNA.”

F or the longest time, Europeans thought that the sun revolved around the Earth. Their culturally attuned eyes saw this as obvious and unquestionably true. Just as astronomers now know that’s not true, nearly all population geneticists know that dividing people into races neither explains nor describes human genetic variation.

Y et this idea of race-as-genetics will not die. For decades, it has been exposed to the sunlight of facts, but, like a vampire, it continues to suck blood—not only surviving but causing harm in how it can twist science to support racist ideologies. With apologies for the grisly metaphor, it is time to put a wooden stake through the heart of race-as-genetics. Doing so will make for better science and a fairer society.

I n 1619, the first people from Africa arrived in Virginia and became integrated into society. Only after African and European bond laborers unified in various rebellions did colony leaders recognize the “need” to separate laborers. “Race” divided indentured Irish and other Europeans from enslaved Africans, and reduced opposition by those of European descent to the intolerable conditions of enslavement. What made race different from other prejudices, including ethnocentrism (the idea that a given culture is superior), is that it claimed that differences were natural, unchanging, and God-given. Eventually, race also received the stamp of science.

Swedish taxonomist Carl Linnaeus divided humanity up into racial categories according to his notion of shared essences among populations, a concept researchers now recognize has no scientific basis. Wikimedia Commons

O ver the next decades, Euro-American natural scientists debated the details of race, asking questions such as how often the races were created (once, as stated in the Bible, or many separate times), the number of races, and their defining, essential characteristics. But they did not question whether races were natural things. They reified race, making the idea of race real by unquestioning, constant use.

I n the 1700s, Carl Linnaeus, the father of modern taxonomy and someone not without ego, liked to imagine himself as organizing what God created. Linnaeus famously classified our own species into races based on reports from explorers and conquerors.

T he race categories he created included Americanus, Africanus, and even Monstrosus (for wild and feral individuals and those with birth defects), and their essential defining traits included a biocultural mélange of color, personality, and modes of governance. Linnaeus described Europeaus as white, sanguine, and governed by law, and Asiaticus as yellow, melancholic, and ruled by opinion. These descriptions highlight just how much ideas of race are formulated by social ideas of the time.

I n line with early Christian notions, these “racial types” were arranged in a hierarchy: a great chain of being, from lower forms to higher forms that are closer to God. Europeans occupied the highest rungs, and other races were below, just above apes and monkeys.

S o, the first big problems with the idea of race are that members of a racial group do not share “essences,” Linnaeus’ idea of some underlying spirit that unified groups, nor are races hierarchically arranged. A related fundamental flaw is that races were seen to be static and unchanging. There is no allowance for a process of change or what we now call evolution.

T here have been lots of efforts since Charles Darwin’s time to fashion the typological and static concept of race into an evolutionary concept. For example, Carleton Coon, a former president of the American Association of Physical Anthropologists, argued in The Origin of Races (1962) that five races evolved separately and became modern humans at different times.

O ne nontrivial problem with Coon’s theory, and all attempts to make race into an evolutionary unit, is that there is no evidence. Rather, all the archaeological and genetic data point to abundant flows of individuals, ideas, and genes across continents, with modern humans evolving at the same time, together.

In this map, darker colors correspond to regions in which people tend to have darker skin pigmentation. Reproduced with permission from Dennis O’Neil.

A few pundits such as Charles Murray of the American Enterprise Institute and science writers such as Nicholas Wade, formerly of The New York Times, still argue that even though humans don’t come in fixed, color-coded races, dividing us into races still does a decent job of describing human genetic variation. Their position is shockingly wrong. We’ve known for almost 50 years that race does not describe human genetic variation.

I n 1972, Harvard evolutionary biologist Richard Lewontin had the idea to test how much human genetic variation could be attributed to “racial” groupings. He famously assembled genetic data from around the globe and calculated how much variation was statistically apportioned within versus among races. Lewontin found that only about 6 percent of genetic variation in humans could be statistically attributed to race categorizations. Lewontin showed that the social category of race explains very little of the genetic diversity among us.

F urthermore, recent studies reveal that the variation between any two individuals is very small, on the order of one single nucleotide polymorphism (SNP), or single letter change in our DNA, per 1,000. That means that racial categorization could, at most, relate to 6 percent of the variation found in 1 in 1,000 SNPs. Put simply, race fails to explain much.

I n addition, genetic variation can be greater within groups that societies lump together as one “race” than it is between “races.” To understand how that can be true, first imagine six individuals: two each from the continents of Africa, Asia, and Europe. Again, all of these individuals will be remarkably the same: On average, only about 1 out of 1,000 of their DNA letters will be different. A study by Ning Yu and colleagues places the overall difference more precisely at 0.88 per 1,000.

The circles in this diagram represent the relative size and overlap in genetic variation in three human populations. The African population circle (blue) is largest because it contains the most genetic diversity. Genetic diversity in European (orange) and Asian (green) populations is a subset of the variation in Africa. Reproduced by permission of the American Anthropological Association. Adapted from the original, which appeared in the book RACE. Not for sale or further reproduction.

T he researchers further found that people in Africa had less in common with one another than they did with people in Asia or Europe. Let’s repeat that: On average, two individuals in Africa are more genetically dissimilar from each other than either one of them is from an individual in Europe or Asia.

Homo sapiens evolved in Africa the groups that migrated out likely did not include all of the genetic variation that built up in Africa. That’s an example of what evolutionary biologists call the founder effect, where migrant populations who settle in a new region have less variation than the population where they came from.

G enetic variation across Europe and Asia, and the Americas and Australia, is essentially a subset of the genetic variation in Africa. If genetic variation were a set of Russian nesting dolls, all of the other continental dolls pretty much fit into the African doll.

W hat all these data show is that the variation that scientists—from Linnaeus to Coon to the contemporary osteoporosis researcher—think is “race” is actually much better explained by a population’s location. Genetic variation is highly correlated to geographic distance. Ultimately, the farther apart groups of people are from one another geographically, and, secondly, the longer they have been apart, can together explain groups’ genetic distinctions from one another. Compared to “race,” those factors not only better describe human variation, they invoke evolutionary processes to explain variation.

T hose osteoporosis doctors might argue that even though socially defined race poorly describes human variation, it still could be a useful classification tool in medicine and other endeavors. When the rubber of actual practice hits the road, is race a useful way to make approximations about human variation?

W hen I’ve lectured at medical schools, my most commonly asked question concerns sickle cell trait. Writer Sherman Alexie, a member of the Spokane-Coeur d’Alene tribes, put the question this way in a 1998 interview: “If race is not real, explain sickle cell anemia to me.”

In sickle cell anemia, red blood cells take on an unusual crescent shape that makes it harder for the cells to pass through small blood vessels. Mark Garlick/Science Photo Library/ AP Images

O K! Sickle cell is a genetic trait: It is the result of an SNP that changes the amino acid sequence of hemoglobin, the protein that carries oxygen in red blood cells. When someone carries two copies of the sickle cell variant, they will have the disease. In the United States, sickle cell disease is most prevalent in people who identify as African American, creating the impression that it is a “black” disease.

Y et scientists have known about the much more complex geographic distribution of sickle cell mutation since the 1950s. It is almost nonexistent in the Americas, most parts of Europe and Asia—and also in large swaths of Northern and Southern Africa. On the other hand, it is common in West-Central Africa and also parts of the Mediterranean, Arabian Peninsula, and India. Globally, it does not correlate with continents or socially defined races.

I n one of the most widely cited papers in anthropology, American biological anthropologist Frank Livingstone helped to explain the evolution of sickle cell. He showed that places with a long history of agriculture and endemic malaria have a high prevalence of sickle cell trait (a single copy of the allele). He put this information together with experimental and clinical studies that showed how sickle cell trait helped people resist malaria, and made a compelling case for sickle cell trait being selected for in those areas. Evolution and geography, not race, explain sickle cell anemia.

W hat about forensic scientists: Are they good at identifying race? In the U.S., forensic anthropologists are typically employed by law enforcement agencies to help identify skeletons, including inferences about sex, age, height, and “race.” The methodological gold standards for estimating race are algorithms based on a series of skull measurements, such as widest breadth and facial height. Forensic anthropologists assume these algorithms work.

Skull measurements are a longstanding tool in forensic anthropology. Internet Archive Book Images/Flickr

T he origin of the claim that forensic scientists are good at ascertaining race comes from a 1962 study of “black,” “white,” and “Native American” skulls, which claimed an 80–90 percent success rate. That forensic scientists are good at telling “race” from a skull is a standard trope of both the scientific literature and popular portrayals. But my analysis of four later tests showed that the correct classification of Native American skulls from other contexts and locations averaged about two incorrect for every correct identification. The results are no better than a random assignment of race.

T hat’s because humans are not divisible into biological races. On top of that, human variation does not stand still. “Race groups” are impossible to define in any stable or universal way. It cannot be done based on biology—not by skin color, bone measurements, or genetics. It cannot be done culturally: Race groupings have changed over time and place throughout history.

S cience 101: If you cannot define groups consistently, then you cannot make scientific generalizations about them.

W herever one looks, race-as-genetics is bad science. Moreover, when society continues to chase genetic explanations, it misses the larger societal causes underlying “racial” inequalities in health, wealth, and opportunity.

T o be clear, what I am saying is that human biogenetic variation is real. Let’s just continue to study human genetic variation free of the utterly constraining idea of race. When researchers want to discuss genetic ancestry or biological risks experienced by people in certain locations, they can do so without conflating these human groupings with racial categories. Let’s be clear that genetic variation is an amazingly complex result of evolution and mustn’t ever be reduced to race.

S imilarly, race is real, it just isn’t genetic. It’s a culturally created phenomenon. We ought to know much more about the process of assigning individuals to a race group, including the category “white.” And we especially need to know more about the effects of living in a racialized world: for example, how a society’s categories Race is real, it just isn’t genetic. It’s a culturally created phenomenon. and prejudices lead to health inequalities. Let’s be clear that race is a purely sociopolitical construction with powerful consequences.

I t is hard to convince people of the dangers of thinking race is based on genetic differences. Like climate change, the structure of human genetic variation isn’t something we can see and touch, so it is hard to comprehend. And our culturally trained eyes play a trick on us by seeming to see race as obviously real. Race-as-genetics is even more deeply ideologically embedded than humanity’s reliance on fossil fuels and consumerism. For these reasons, racial ideas will prove hard to shift, but it is possible.

Over 13,000 scientists have come together to form—and publicize—a consensus statement about the climate crisis, and that has surely moved public opinion to align with science. Geneticists and anthropologists need to do the same for race-as-genetics. The recent American Association of Physical Anthropologists’ Statement on Race & Racism is a fantastic start.

I n the U.S., slavery ended over 150 years ago and the Civil Rights Law of 1964 passed half a century ago, but the ideology of race-as-genetics remains. It is time to throw race-as-genetics on the scrapheap of ideas that are no longer useful.

W e can start by getting my friend—and anyone else who has been denied—that long-overdue bone density test.


Watch the video: Tom Wolfe on why Darwins evolution theory is a myth (January 2022).