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narwhal hybrid.png

a: beluga skull b. “narluga hybrid” c. male narwhal skull.

In the 1980s, an Inuit subsistence hunter in Greenland killed three gray whales that looked suspiciously like belugas at first. However, they were oddly gray. The fins resembled a beluga’s, while the tail looked like that of a narwhal.

The hunter kept one of the skulls, eventually donating it to science, where became the property of the Greenland Fisheries Research Institute. A scientist working for that institute, Mads Peter Heide-Jørgensen,hypothesized that this skull came from a hybrid between a narwhal and a beluga.

It was only today that a study was released in the journal Nature that revealed that this whale was indeed a hybrid. The DNA analysis revealed that male beluga mated with a female narwhal to produce the creature.

The skull was quite strange. Belugas have 40 homodont teeth. Narwhals are toothless, except males. The males have one really long canine tooth that sticks out as a tusk. Sometimes, they have two, but most have only one true tooth. It is spiraled like what is expected form the mythical unicorn. They do have only a few vestigial teeth.

The hybrid had 18 teeth, many of which were pointed out horizontally and spiraled like the vestigial teeth of the narwhal.

Isotopic analysis also revealed that the hybrid had a different diet from either parent species, both of which catch fish or squid in the open water. The beluga hunts fish at depths of up to 500 meters, while the narwhal hunts fish or squid at depths exceeding 800 meters. The isotopic analysis revealed that the narluga was eating mostly benthic prey, which means it was eating mostly shellfish from the sea floor.

So this study raises so many questions. Analysis of the narwhal genome revealed that gene flow between the two species stopped between 1.25 and 1.65 million years ago. The initial split happened around 4 million years ago, and that study thought that an viable hybrids would be unable to reproduce. However, the authors of the study cautioned that a larger sample size of individual narwhal and beluga genomes from across their range might reveal more recent dates on when gene flow stopped (if it did at all).

So it is not entirely clear that this hybrid would have been sterile, but we also have no further evidence of hybrids anywhere else.  It is quite possible that these hybrids could be fertile, and if they are, climate change could cause the eventual genetic extinction of the narwhal.

The morphology and feeding behavior this odd whale might point to the origins of the narwhal. Perhaps the ancestral narwhal was a benthic feeding whale that later lost its teeth to become a whale that hunts squid and fish at great depths with an almost toothless mouth.

Having teeth like the hybrid is a great adaptation for this particular diet, because the forward pointing teeth can poke around and dislodge shellfish more easily.

If these hybrids are fertile, then one could see the eventual development of a hybrid whale species that has its own niche as a benthic feeder in the arctic.

It is an amazing find, and chances are there will be more discovered. Further, as scientists examine genomes from belugas and narwhals from a wide geographic distribution, we might see evidence of some hybridization.

Hybridization could also increase genetic diversity in narwhals, but if these hybrids must eat a fundamentally different diet than narwhals do, it might become difficult for these hybrids to add their genes to narwhal populations. They just cannot hang out for extensive periods of time, before they have to split off and engage in divergent feeding behavior.

So this discovery does generate lots of speculation and raises several important questions that need to be addressed.

Pretty cool.

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yakutian megafaunal wolf

The Siberian Times reports that the head of a massive wolf was discovered in the permafrost in Yakutia (Sakha Republic of Russia).  The head includes much of the soft tissue, as well as its golden-colored fur. The head is 40 cm (15. 7 inches long), which is pretty large when compared to modern wolf specimens.

Researchers in Russia and Japan will be examining the DNA from the soft tissue to see where it fits in modern wolf and dog phylogeny of which there are still many questions.

This wolf is a good example of what have been termed “megafaunal wolves,” very large gray wolves that lived during the Pleistocene. Robert Wayne of UCLA, a leading canid molecular geneticists, thinks that some form of Pleistocene megafaunal wolf is the progenitor of the domestic dog.  These wolves would have been expert hunters of large bison, reindeer, and horses, and they may have been semi-nomadic, following large herds of ungulates across the steppes and taiga. These semi-nomadic wolves would have been quite easily attached to humans, who were hunting and traveling in much the same way.

Also of note, this wolf has golden colored fur.  In 2015, I postulated a speculative hypothesis that the original Pleistocene wolves were more often golden in color, rather than gray.  When humans started hunting wolves extensively during the Neolithic and into modern times, wolves that were gray were selected for because they could more easily hide from human hunters. Gray color in the dead of winter in many European and Western Asian forests would have been great camouflage against the winter tree trunks and undergrowth of the forest.

Some wolves, especially tundra wolves from northern Russia and Finland, are still often golden in color, as are those in Central Asia.

Golden sable color is quite widespread in domestic dogs, but it is far less common in wolves. So it is quite possible that this coloration is so dominant in domestic dogs because the wolves that gave rise to them were this color.

This massive wolf with golden fur certainly adds some credence to my speculations, but only time will tell what this ancient, massive wolf’s head has in store for us.

But is an amazing find. No doubt about it!

Update: Researchers in Sweden, not Japan or Russia, will be examining its DNA. 

 

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no god

I don’t believe in the supernatural.  The natural is fantastical enough without needing some anthropomorphic figure that controls all forces of nature and also justice.  The more I see of humanity and nature, the less I believe that such a figure is likely, and such a figure could not be contained in the ancient edicts of scripture and clergy. It is not that I am rebellious or angry. It’s that I can no longer be illusioned.

To not believe and live in Norway is a lot different than to be in the same theological position and happen to live in West Virginia.  I no longer do, of course, but when I did live there, I felt that I always had to keep my mouth shut.

I no longer feel so constrained. I am an atheist. I don’t believe in God or the Devil.  I came to this conclusion in my 20s, though by the time I was 16, my own version of Christianity had a deist divinity and the Christ figure was but a metaphor.

I never was “born again,” but when I was younger I pretended that I was. Maybe, it was all like make-believe in the literal sense of the two words. Maybe if I just made myself believe it would all work out.

I knew things were going to be strange when I was the only student in my tenth grade biology class who believed that humans resulted from evolution. Most of my classmates either believed in creationism, but the more enlightened ones had some belief that all other organisms evolved. Humans did not. Humans were still a special creation of God.

Christianity and I were never good fits. I remember getting in trouble for praising God for my new pet duck when the pastor asked for praises at the beginning of worship service. I was told that this was not something one praised, but when you’re in the first grade and crazy about animals, there couldn’t be anything to be happier about, right?

My parents were uncomfortable with me leaving my dinosaur figurines behind the rear glass of their car.  They were okay with evolution. We even went to a church that was okay with evolution in terms of doctrine, but lots of people who went to that church were not okay with it.  Some of them may have doubted whether dinosaurs existed at all  and would think that my parents were doing me a great disservice.

I tried really hard to be a Christian and remain curious and skeptical about the world. I found that I could not reconcile the things I found out about nature with the cosmos as described in the Bible.

Further, I came to resent Christians’ hateful obsession with homosexuality. Though I am hetero and cis, I realize that both these things are not of my own choosing. I don’t remember when I chose to be into girls or why I am okay with being stinky old man. I had an epiphany in the eight grade that whatever God I worshiped could not damn people for their sexuality. That would be like damning someone for the color of their skin.

I spent my adolescence trying to reconcile my values and knowledge with Christianity. I wound up discarding lots of Christian doctrine. And then I realized that I should discard the whole thing.

Finding values based in secular morality has not been tough for me. However, realizing that others could not see that their own morality was ultimately secular– they wouldn’t kill  or rape someone because God told them to– was one of the hardest things to deal with.

At one point in my life I was active in the Democratic Party. As an undergraduate I campaigned hard for John Kerry. I had been told that West Virginia was in play, and that I should be doing all I could to get people to vote Democrat.

It turned out that West Virginia had undergone a political sea change in the years in which I was maturing into a young activist. For most of my childhood, no one would admit to being a Republican for fear that you’d be cast in league with Herbert Hoover, the great villain of the 1930s.  But in those years in which I was becoming an adult, the state shifted hard to the right. Fundamentalist Christianity and a dying coal industry were working hard among the rural populace.

I attended college with many kids who were first generation college students. I was aghast at the Iraq War, and many of them were too.

However, when I asked them to vote Democrat, they would say something like “Bush is a Christian.”  I got that answer so often that I wondered if there would ever be any hope for humanity if people could use that religious identification as a justification for political choices.

I was growing more and more skeptical about the world.  And I realized at one point that I needed to let it go.

And I was a quiet atheist for several years, but one day, while perusing the new Youtube on my laptop, I came across Kent Hovind’s lecture “Dinosaurs and the Bible.” The man was an obvious huckster, a true flimflam man from the days patent medicine, who also sold his own patent medicine in the form of laetrile, a supposed cancer cure that is actually the cyanide in the seeds of fruit-bearing plants.

When I finished watching that monstrosity, I was certain that I could never be brought into believing again. I would have to hide my atheism, but at some point, I did become more public with it.

I am not ashamed that I don’t believe in God and that I never will again. As time marches on, my nation is becoming more and more secular, just like the other formerly majority protestant countries in Europe.  It has just taken the US a lot longer.

The fact that so much of Christianity is now tied up in the worship of Trump pretty much means the eventual downfall of the institution in the United States. His are the politics of the old and angry, stilling holding onto a world that will never exist again.

I will never learn to live in God. I will instead learn to live with the reality that my time is finite. In that finite existence, I must be who I want to be and nothing else. If this is offensive, then you stand to be offended. But I will not hide what I am and what I seek to be.

Someday, I will cease to exist. The same goes for the oak tree that grows tall on a distant ridge. Its acorns feed the deer, the squirrels, the turkeys, and bears. It will live through many generations of its beneficiaries then on some windy day in March, the great wooden edifice will come crashing down. It will decompose into the leaf litter, restoring its elements to the soil from whence it came.

I am no more significant in the grand scheme than an oak or the squirrels that bury its acorns. We are all biotic beings, produced through the great story of evolution.

Who could need anything else? Why invoke some supernatural thing, when the natural explanation is so wondrous and so complete?

And that’s where I fall on that great question. I wager this, because I cannot live in the unlikely wager that the Bible is correct, when it is wrong about so many fundamental things. Not just wrong about biology or cosmology but wrong about moral questions too. Slavery is not condemned in the Bible nor is genocide. Indeed, both are commanded at  various books.

So this is where I stand. A heathen but an intellectually honest one.

 

 

 

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Julie Dickinson of Ruff Sketch Design did portraits of our dogs.  They are so nice!

Streamer:

streamer

Quest:

quest portrait

Poet:

poet potrait

Erika:

Erika

Zoom:

zoom

 

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box turtle

Possibly the greatest debate in all vertebrate taxonomy is classifying the turtle. If you were to ask an expert about where turtles belong, well, it will depend upon the expert and which papers this expert has recently read.

That’s because the literature on turtles is definitely divided. Morphological comparison studies, some of which have used rather complex statistical analysis of characters, have generally placed them closer to Lepidosaurs.  The most common Lepidosaurs are squamates, which are better known as snakes and lizards, and there is another Lepidosaur order with exactly one species left in it. Rhynchocephalia is this order, and it includes exactly one extant species, the tuatara of New Zealand.

Molecular studies have generally placed the turtles either into or close to Archosaurs.  Extant Archosaurs are the crocodilians and birds. All dinosaurs and pterosaurs were also Archosaurs, and birds, which are the only living dinosaurs, are certainly Archosaurs.

One would think that molecular studies would solve this problem, but it really doesn’t.  The problem is that turtles evolve quite slowly, and trying to figure out divergence times based upon mutation rates could result in inaccurate conclusions.

So no one really has a way to resolve this conflict.

And if you were to ask me, I would say, well, I don’t know. We have some ideas, but they are in conflict. And we have no way to resolve them at this time.

But that’s science for ya.

 

 

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marsh rabbit

One of the most interesting aspects of North American wildlife is the wide diversity of rabbit species. The most common rabbit species in the Eastern and Midwestern US is the Eastern cottontail (Sylvilagus floridanus), but it only one many North American rabbits.  The genus of cottontails, Sylvilagus, includes many regional and specialized forms. In the Allegheny mountains, there are Appalachian cottontails (S. obscurus), and in parts of New England and New York State, one can find the New England cottontail (S. trasitionalis).  In the West, we have desert cottontails (S. audubonii) and the mountain cottontail (S. nutallii) in the interior, and the brush rabbit (S. bachmani) along the Pacific coast.

However, those are pretty banal bunnies. Over the past week or so, though, I’ve seen the video clip from the CBC showing a swamp rabbit swimming strongly to evade predators, So I thought I would take some time to talk about our “water rabbits,” the two species of cottontail have evolved to live in the Southeastern swamps and marshes.

From Southeastern Virginia to Florida and as far west as Mobile Bay, the short-eared marsh rabbit (S. palustris) lives makes its home among fresh and brackwater marshes and swamps.  They live among the cattails and mangroves and thickets of black gum and magnolia. They tend to be smaller than Eastern cottontails, which can also appear in similar environments, and their tails are usually shorter and are almost never fully white.

The swamp rabbit (S. aquaticus) by contrast is the largest cottontail species, averaging double the mass of an Eastern cottontail.  It is much larger than the marsh rabbit. The only states where both of these species are found are South Carolina, Georgia,  and Alabama, but there isn’t much range overlap. This rabbit likes cypress swamps and lowland river floodplains. They range as far north as southern Illinois and Indiana, but they are particularly common in the Mississippi Delta.

These two species are considered sister taxa, and these two rabbits are placed in the subgenus Tapeti. This subgenus includes mostly cottontails from Mexico on south, and these two water rabbits are the only two members of these subgenus found in the United States. This classification has been determined through a limited mitochondrial DNA study. 

Of course, I would like to see more studies of the various cottontail rabbits’ genomes, but this classification is the only one currently accepted.

I should note that one subspecies of marsh rabbit (Sylvilagus palustris hefneri), which is found in the Lower Keys of Florida, is considered an endangered species.  It is named for Hugh Hefner, whose corporation donated a substantial sum to research this rabbit.

This rabbit is vulnerable because of predation by feral cats, as well as other invasive predators, such as boa constrictors and fire ants. Invasive plants have also destroyed the undergrowth that these rabbits use to hid from their predators. Many of these rabbits are also victims of traffic.

Maybe this rabbit would get better attention as an endangered species if conservationist played up its connection to Hugh Hefner. We could call it “The Campaign to Save the Real Playboy Bunny. ”

The swamp rabbit has a following among beagle houndsman in much of its range, and these rabbits are taken as monster trophies in much the same way that Eastern deer hunters who have hunted white-tails their whole lives will go west in search of a monster mule deer.  The old way of hunting both swamp and marsh rabbits was to burn them out of their marsh grass hideouts, but wildlife management agencies regulate the hunting of both species.

So when you see that clip of the swamp rabbit swimming think of both of these rabbits. They are amazing creatures, perfectly adapted to living near water and using their strong swimming abilities to evade their most aggressive predators.

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4,000 year old dog

The skull of a 4,000 year-old dog has been used to reconstruct what its head may have looked like.

The dog was quite wolf-like and described by the BBC as being about “the size of a large collie.” In the UK, “collie” almost always refers to border collies, so this dog probably would have been on the large side of a medium-sized dog.

The dog’s skull was found at Cuween Hill Chambered Cairn on on Mainland, Orkney, off the northern coast of Scotland. 3D images of the skull were use to make the reconstruction, which was created in clay. The artist then made the fur look like that of a European wolf, which is not entirely unreasonable given the morphology of the skull itself.

The dog may have been used to tend sheep or guard settlements. It was clearly a respected creature in the society that interred in the tomb. Maybe it was a valued working animal or simply a totem of its people.

Whatever it was, it was clearly more wolf-like that one might have expected from a dog from this late a date. The Ancient Egyptians, who were contemporaries of these Orkney cairn tomb builders, were already breeding dogs that were quite distinct from wolves.

But the truth of the matter is that this dog was significantly smaller than most modern and contemporary European wolves, and the mainland of Scotland was full of wolves that were probably still interbreeding with domestic dogs on occasion at this time.

So the Orkney Islanders from 4,000 years ago clearly had dogs, but I imagine this dog as being something like a Norwegian elkhound, a laika, or one of the old German herding dogs, like the Thuringian sheepdog.

I would love to see more reconstructions from ancient dogs skulls.  I would love to see the Goyet Cave canid and the Razboinichya Cave “dog” undergo a similar reconstruction.

Yes, this is art, but it is art that is informed through science.

 

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