Michael J. Behe's Blog, page 485

Proposed new definition of life would include embryos, exclude AI

Some scientists have been doing some thinking about the NASA definition of life (“a self-sustaining chemical system capable of Darwinian evolution”) and wondering if it needs a rethink in the age of advanced robotics:

AI robots would not fit into our definition because human beings can control all aspects of computer functions. There is no uncertainty, nor unknowability, with AI robots. AI-based human robots can be programed to replicate themselves and even can be programed to terminate. However, robots do not sense “mutations” or engage in any natural selection process and, therefore, would not meet our criteria as “living.”John D. Loike, Robert Pollack, “Opinion: How to Define Life” at The Scientist

But lawyer and ethicist Wesley J. Smith points out, embryos would:

Speaking of moral value, the professors’ proposed definition would certainly include the earliest human embryos, their status as “human life” often denied by those who wish to justify their wanton destruction or casual instrumental use as natural resources. Wesley J.Smith, “Scientists’ Definition of Life Excludes AI, but Includes Embryos” at Mind Matters News

To be honest, we were fully expecting that the next thing we’d hear is that AI is life and embryos aren’t. These guys must be doing some thinking.

See also: Gerald Joyce No Longer Uses The NASA “Must Show Darwinian Evolution” Definition Of Life

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Narwhal thriving despite low genetic diversity

Male narwhal/wildestanimal , Fotolia

A narwhal is an Arctic whale with a very long tusk (a tooth) on its forehead. From ScienceDaily:

Low genetic diversity has historically been viewed as a species’ death sentence because it was thought that when members of a species have less DNA variation for natural selection to act on, they would struggle to adapt to changes in their surroundings. But this research suggests it might be more complicated than that.

“There’s this notion that in order to survive and be resilient to changes, you need to have high genetic diversity, but then you have this species that for the past million years has had low genetic diversity and it’s still around — and is actually relatively abundant,” says Eline Lorenzen, an associate professor and curator at the Natural History Museum of Denmark. Currently, the population estimate of narwhals places them at around 170,000 individuals, enough to change their IUCN Red List status from “Near Threatened” to “Least Concern” last year.

“This shows us that just looking at the number of individuals isn’t indicative of the genomic diversity levels of a species, but also looking at the genomic diversity levels isn’t indicative of the number of individuals. Equating those two doesn’t seem to be quite as simple as previously thought,” Lorenzen says.

Interestingly, the low genetic diversity found in narwhals appears to be unique to the species; several other Arctic species, including their closest relative, the beluga, all have higher levels of genomic diversity. Paper. (access?) – (open access) More.

Here’s a possible history:

So what, exactly, is going on with the so-called “unicorns of the sea”? A population boom tens of thousands of years ago might be key to understanding the species puzzling lack of diversity, the study authors suggest. Through scientific modelling, the team was able to determine that narwhals began to experience a slow but constant population decline around two million years ago; by 600,000 years ago, only around 5,000 individuals were left. Narwhal numbers began to pick up around 100,000 years ago, roughly coinciding with the onset of the last glacial period, which in turn suggests that the population uptick was caused by “an environmental driver, possibly linked to an increase in Arctic sea ice,” the researchers write. Then, between 30,000 and 40,000 years ago, narwhal numbers started rising rapidly—and, according to the researchers, “genetic diversity may not have had time to increase accordingly.”

Narwhals may have been able to fare well despite their loss of genetic diversity because the population decline that began millions of years ago happened slowly, giving the animals time to “evolve different mechanisms to cope with their limited genome,” says Michael Vincent Westbury, lead study author and a postdoctoral researcher at the Natural History Museum of Denmark. Brigit Katz, “Narwhals Have Low Genetic Diversity—and They’re Doing Fine ” at Smithsonian Magazine

It turns out that low genetic diversity is not necessarily a death sentence. It depends on what else is going on, perhaps.

By the way, we still don’t know why the narwhal has a three-metre tusk (tooth).

See also: Darwin vs. the polar bear

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Researchers: Rare ocean life forms breathe arsenic in low oxygen environments

Arsenic is a chemical element/
 Tomihahndorf (CC BY-SA 3.0 )

From ScienceDaily:

“We’ve known for a long time that there are very low levels of arsenic in the ocean,” said co-author Gabrielle Rocap, a UW professor of oceanography. “But the idea that organisms could be using arsenic to make a living — it’s a whole new metabolism for the open ocean.”

The researchers analyzed seawater samples from a region below the surface where oxygen is almost absent, forcing life to seek other strategies. These regions may expand under climate change.

“In some parts of the ocean there’s a sandwich of water where there’s no measureable oxygen,” Rocap said. “The microbes in these regions have to use other elements that act as an electron acceptor to extract energy from food.”

The most common alternatives to oxygen are nitrogen or sulfur. But Saunders’ early investigations suggested arsenic could also work, spurring her to look for the evidence…

Results suggest that arsenic-breathing microbes make up less than 1% of the microbe population in these waters. The microbes discovered in the water are probably distantly related to the arsenic-breathing microbes found in hot springs or contaminated sites on land.

“What I think is the coolest thing about these arsenic-respiring microbes existing today in the ocean is that they are expressing the genes for it in an environment that is fairly low in arsenic,” Saunders said. “It opens up the boundaries for where we could look for organisms that are respiring arsenic, in other arsenic-poor environments.”

Biologists believe the strategy is a holdover from Earth’s early history. During the period when life arose on Earth, oxygen was scarce in both the air and in the ocean. Oxygen became abundant in Earth’s atmosphere only after photosynthesis became widespread and converted carbon dioxide gas into oxygen.

Early lifeforms had to gain energy using other elements, such as arsenic, which was likely more common in the oceans at that time.
Paper. (paywall) – Jaclyn K. Saunders, Clara A. Fuchsman, Cedar McKay, Gabrielle Rocap. Complete arsenic-based respiratory cycle in the marine microbial communities of pelagic oxygen-deficient zones. Proceedings of the National Academy of Sciences, 2019; 201818349 DOI: 10.1073/pnas.1818349116 More.

A friend tells us this looks like a new find and not to be confused with a previous one that didn’t hold up.

What’s amazing is the way life, once started, exploits every avenue, and yet how does it get started?

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Researchers: What’s INSIDE a planet determines habitability

exoplanet Barnard’s star B (artist)/ ESO, M. Kornmesser

Yesterday, we noted that Rob Sheldon disputes the claim (said it was “bunk”) that ocean planets would be sterile due to lack of nutrients from land.

A team of Carnegie investigators thinks that it’s what’s inside the planet that counts:

It all starts with the formation process. Planets are born from the rotating ring of dust and gas that surrounds a young star. The elemental building blocks from which rocky planets form—silicon, magnesium, oxygen, carbon, iron, and hydrogen—are universal. But their abundances and the heating and cooling they experience in their youth will affect their interior chemistry and, in turn, things like ocean volume and atmospheric composition. “One of the big questions we need to ask is whether the geologic and dynamic features that make our home planet habitable can be produced on planets with different compositions,” Driscoll explained. The Carnegie colleagues assert that the search for extraterrestrial life must be guided by an interdisciplinary approach that combines astronomical observations, laboratory experiments of planetary interior conditions, and mathematical modeling and simulations. “ When it Comes to Planetary Habitability, It’s What’s Inside That Counts” at Carnegie Science

Well, we can always use more good information.

See also: Rob Sheldon: That “sterile exoplanet ocean” paper is bunk! The amazing thing about life, is that it is always so very adaptable. Who knew that bugs can live at 140C, or with metabolism so slow it takes centuries to replicate?

and

Exoplanets: Those water worlds would have sterile oceans too… Researchers: An all-ocean planet would be sterile due to lack of nutrients leached from land.

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Denisovan jawbone from 160 kya starts to talk…

Well, you have to love National Geographic’s title: Mysterious ancient human found on the ‘roof of the world’

Their view: “ fossil jaw shatters records for the earliest inhabitants of the Tibetan Plateau—and gives new insights into the enigmatic Denisovans.”

The Denisovans, only discovered a few years ago, were widespread and lived at a high altitude:

The research marks the first time an ancient human has been identified solely through the analysis of proteins. With no usable DNA, scientists examined proteins in the specimen’s teeth, raising hopes that more fossils could be identified even when DNA is not preserved…

Until now, everything scientists have learnt about Denisovans has come from a handful of teeth and bone fragments from Denisova Cave in Russia’s Altai Mountains. DNA from these remains revealed that the Denisovans were a sister group to Neanderthals, both descending from a population that split away from modern humans about 550,00–765,000 years ago. And at Denisova Cave, the two groups seem to have met and interbred: a bone fragment described last year belonged an ancient-human hybrid individual who had a Denisovan father and Neanderthal mother. Matthew Warren, “Biggest Denisovan fossil yet spills ancient human’s secrets” at Nature

In short, we really know what happened but we at least know who some of the players were.

This Tibetan find was the first time remnants of this gorup were found far from the Denisova Cave, but that said,

“Given that Denisovan DNA is found in present-day people all over Asia, it was almost a matter of time until someone would find a Denisovan at some other place than Denisova Cave,” Svante Pääbo, a geneticist at the Max Planck Institute for Evolutionary Anthropology who led the team that first discovered the Denisovan species, writes in an email to The Scientist. Shawna Williams, “Denisovan Fossil Identified in Tibetan Cave” at The Scientist

One of the finders tells us

But the most extraordinary aspect of our findings, in my opinion, is the demonstration that such archaic hominins could successfully live in this challenging high-altitude environment, more than 120,000 years before modern H. sapiens settled on the Tibetan Plateau. It seems that a gene variant that helps modern populations on the Tibetan Plateau to adapt to high-altitude hypoxia was inherited from these Denisovans.

A new phase in the deciphering of human evolution in Asia has begun. Human evolution in this part of the world is much more complex than was thought; the simplistic model of a local and direct evolution from Homo erectus to present-day Asians needs to be abandoned. And from the Baishiya Karst Cave, there will surely be more discoveries to come. Jean-Jacques Hublin, “How We Found an Elusive Hominin in China” at Sapiens

Yes, the simplistic stories are definitely getting updated:

There are, however, limits to what can be said from proteins. Denisovans had a stunning amount of diversity. A study published earlier this year suggested that what we call Denisovans might actually be three distinct genetic lines, one of which is nearly as different from other Denisovans as they are from Neanderthals. But the similarity of proteins across groups and through generations makes it difficult to pinpoint precisely how similar the owner of the jaw is to these three Denisovan lines—or if it was from yet another sister group.Maya Wei-Haas, “Mysterious ancient human found on the ‘roof of the world’” at National Geographic

Have you noticed how new finds keep leading us back to ourselves, not to the missing link?

See also: In any Darwinian scheme, someone must be the subhuman. Otherwise, there is no beginning to human history.

Was Neanderthal man fully human? The role racism played in assessing the evidence

and

Do racial assumptions prevent recognizing Homo erectus as fully human?

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Neurosurgeon Michael Egnor: Physicist Sabine Hossenfelder is really confused about free will

We’ve often written about Sabine Hossenfelder, author of Lost in Math: How Beauty Leads Physics Astray, whose take on current physics hype is not to be missed.

But then she decided to tackle a philosophical topic, free will. And, according to neurosurgeon Michael Egnor, who writes a lot on the topic, it didn’t go well:

Actually, her critics have a point. Why does she try to get people to change their minds if they aren’t free in some real sense to change their minds? It makes no sense to reason with someone whose will is wholly composed of “particles” and “equations”:

“I have come to the conclusion that a large fraction of people are cognitively unable to question the existence of free will, and there is no argument that can change their mind. ”

It’s hilarious. She misses the irony that she insists that people “change their minds” by accepting her assertion that they… can’t change their minds. Michael Egnor, “Can physics prove there is no free will?” at Mind Matters News

It really is quite funny. And physicists should stick to physics.

Also by Dr. Michael Egnor on free will:

Does “alien hand syndrome” show that we don’t really have free will?

How can mere products of nature have free will?

Does brain stimulation research challenge free will?

Is free will a dangerous myth?

and

But is determinism true?

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Rob Sheldon: That “sterile exoplanet ocean” paper is bunk!

drop of water/José Manuel Suárez (CC)

Recently, we pointed to a paper on ocean exoplanets which argued that such ocean planets would have sterile oceansdue to lack of nutrients leached from land.

Our physics color commentator Rob Sheldon had a look and, well, he disagrees:

This paper is simply bunk.

Firstly, we don’t know how life started, much less evolved, so whether ocean planets are sterile or not is just not knowable. The reason the paper says this, of course, is political: NASA is spending big bucks to look for life on Europa, a moon of Jupiter that has a global ocean. If someone can challenge NASA, then at least that person can get funded by NASA to prove himself wrong.

Secondly, we already have counter-examples of life on places that do not have a hydrologic cycle–namely comets. This time we can’t even claim ignorance.

Thirdly, “difficult” for us is not difficult for life. Consider the arsenic-tolerant microbes found in California’s Mono Lake.

The grad student, Felisa Wolf-Simon, who found them, named the bugs GFAJ-1, which stands for “Get Felisa A Job”. Mono Lake is full of arsenic, and she grew them in a nutrient broth that had no phosphorus in it, concluding that they didn’t need phosphorus to grow. Hence the paper.

As it turned out Nature reported 18 months later, these bugs have some really, really good phosphorus scavenging proteins, and could pull phosphorus out of other dead bugs or even the impurities in Felisa’s chemicals. (She didn’t use the ultra-pure chemicals in her experiment because they are prohibitively expensive, and the trace impurities included phosphorus.)

For the record, I went to bat for Felisa, arguing that even though she might not be the most experienced researcher, to the best of her abilities and technique, her bugs were growing without phosphorus. Perhaps she injudiciously made an early pronouncement, but as the editor of Zeitschrift fur Physik said about Stern and Gerlach’s controversial paper on electron spin–they’re young enough to take the risk.

So back to our sterile ocean–if phosphorus is rare, then like GFAJ-1, life will find ways to treasure it. The amazing thing about life, is that it is always so very adaptable. Who knew that bugs can live at 140C, or with metabolism so slow it takes centuries to replicate? The real discovery is not that Mars is sterile or Europa unlikely to have life, but rather that there does not appear to be a single place with liquid water that hasn’t already been colonized by life. And perhaps that is the thing NASA is most afraid of finding.

Rob Sheldon is author of Genesis: The Long Ascent

Exoplanets: Those water worlds would have sterile oceans too… Researchers: An all-ocean planet would be sterile due to lack of nutrients leached from land.

Rob Sheldon: The real reason there is a crisis in cosmology Nearly everything that has failed about the Big Bang model has been added because of bad metaphysics, a refusal to accept the consequences of a beginning. The remaining pieces of the Big Bang model that are failing and which can’t be attributed to bad metaphysics, were added from sheer laziness.

Doubt cast on new “exomoon”: Rob Sheldon explains Sheldon: There are red flags all over this data, but the investigators are standing by their measurement. This is what irreproducible papers look like in physics, and why the same crisis that afflicts other disciplines also afflicts physics.

and

Rob Sheldon: Here’s why physicists are surprised by the universe’s increased expansion rate The two methods differ in that one is “direct” and the other “indirect”. Clearly one or both of them is making a mistake. Since it is hard to find (and people have looked) a reason why the direct method is failing, the feeling is that the indirect method must have a mistake in its model.

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Flagellum vid passes 50k views

Congrats to Philip Cunningham

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Did the Neanderthals have a cult going 130,000 years ago?

About the golden eagle. And they got others to buy into it?

The golden eagle seemingly was a bird of special importance to the Neanderthals. It’s the bird of prey they captured most frequently, and the way it was butchered indicates that it wasn’t sought out purely for food. Importantly, the discovered golden eagle wing bones have cut marks along them. Wing bones contain little meat, so the idea is that what was being sourced were their feathers. Additionally, the bones also contain cut marks between the legs and feet, a sign that the Neanderthals were removing claws and talons. Golden eagle jewelry specifically hasn’t been found, but white-tailed eagle jewelry has, so it’s likely the feathers served a similar purpose…

Co-author Stewart Finlayson, Ph.D., the director of the natural history department at the Gibraltar National Museum, tells Inverse that catching eagles for feathers and talons “suggests symbolic capacities not previously ascribed to Neanderthals.” Sarah Sloat, “Neanderthals May Have Taught Humans to Join a “Cult” 130,000 Years Ago” at Inverse

Okay, “cult” isn’t a designation of praise but it’s way better than how the Neanderthals were thought of in the past. Anyway, we are told that the birds used to snatch Neanderthal children.

Now it is the bird you should worry about.

An article on Neanderthal eagle jewelry here. (Revenge?)

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See also: New film: What if a Neanderthal were alive today?

and

Smithsonian belatedly asks, What do we really know about Neanderthals? What do we know? Well, we know what the science establishment has told us, that’s what. Previously, the science establishment spent a lot of time looking for the Darwinians’ subhumans. At all times, thin on the ground, it would seem. So they drafted the Neanderthals because, well, they were there. Now it seems, they have discharged them.

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Religious Nones: The bigger picture shows increasing polarization

On recent Sundays, we’ve been pointing to discussions of the rise of the Religious Nones (people who say they have no religion) – and what that means and doesn’t mean. (Here and here, for example).

It doesn’t mean that former theists have become atheists or even that they are likely to. The driving factor is the collapse of mainline Protestantism, leaving people who are vaguely theist without a religious identity. Many questions lie beyond that change but first, a note about identity…

The Catholic Church is in big trouble too. But the nature of the problem is a bit different. “Catholic” is a multigenerational identity. People can think of themselves as Catholic even if no one since their grandparents’ day has ever been to mass. Put another way: They don’t think they’re atheists (that’s scary). They just continue to say they are Catholic—even if they can’t recite the Lord’s Prayer. No one challenges them on the point. Why bother? One suspects it’s roughly similar with Islam in the Middle East.

By contrast, let’s say that no one in your family has darkened the door of a mainline liberal church since your grandmother did, occasonally, in the 1960s. You probably won’t think of yourself as a member. Truth be told, such a church never had much impact on the culture around it. In recent decades, it probably became largely indistinguishable from the surrounding culture from which it got all its ideas. Its disappearance would have little cultural impact.

The rise of the Nones does mean something important, however: Those who care about the Big Questions are more visibly polarized:

Consider, for example, the percentage of Americans who report that their religious affiliation is “Strong.” This percentage has fluctuated a bit over the decades, but the most recent survey puts it at 34 percent, a number that has remained basically unchanged since 1975, when 35 percent of Americans reported a strong religious affiliation. Apparently, the rise of the Nones is not attributable to a decline in religious enthusiasm among the most strongly committed.

By contrast, the decline in the percentage of Americans who say their religious affiliation is only “Somewhat strong” appears steadier, particularly in recent years. In 2006, about 12 percent of Americans told the GSS surveyors that their affiliation was “Somewhat Strong.” In the most recent survey, that percentage has fallen to only 4 percent. That is a significant drop…
Confirmation bias is always a problem when one looks at data like this. Still, the 2018 report suggests that Americans are becoming deeply divided in our attitudes toward religion, a subject about which I’ve written elsewhere. Mark Movsesian, “The Devout and the Nones” at First Things

Movsesian goes on to explain that the divide leaves a deeper mark now on American politics, with Religious Nones being the largest group in the Democratic Party (30%) and 70% of declared Republicans believing in the “God of the Bible.” The “religious left,” incidentally, now seems to be largely an artifact of thinkmags, although it was an important force decades ago.

Visible polarization enables issues to become more politicized than they otherwise could be.

Whatever happens with science issues as a result won’t be dull.

See also: Researchers: Rise In “Religious Nones” Masks Growth In Evangelicalism

and

For The First Time, “No Religion” Is The Most Popular Choice For Americans

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