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Roadkill Forcing Cliff Swallows To Evolve
sciencehabit writes "Cliff swallows that build nests that dangle precariously from highway overpasses have a lower chance of becoming roadkill than in years past thanks to a shorter wingspan that lets them dodge oncoming traffic. That's the conclusion of a new study based on 3 decades of data collected on one population of the birds. The results suggest that shorter wingspan has been selected for over this time period because of the evolutionary pressure put on the population by cars."
That will be the downfall of your species. Those who march in front are merely the meat-shields for the warriors that follow, the first torn down by the musket balls and horse mounted cavalry while those behind remain to actually fight.
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This could be tricky, if this gets classified as a new species, how do we factor in the need for persistant traffic in environmental impact reports? If we cut traffic this species would lose its competitive edge and thus habitat and could become extinct!
Now if only humans would evolve that fast...
Disagreeing with you does not make me a troll.
If I keep on smacking my kids, their arms will get shorter?
...And this is yet another proof that God exists. My prayer circle has spent the last 10 years asking for Divine intervention to halt the senseless deaths of road-adjacent animals. Thanks to our unceasing intervention, He knew to trim a wee bit off the tip of every bird's wings (gradually, of course, so that mommy birds would still recognize their babies - and left longer wings on the sinner birds so that they would die and serve as a warning to others). Praise Jesus!
these evolutionists are just trying to force these lies down your throats.
how can the birds be changed by the overpasses? the bible tells us that the overpasses have existed since the creation of the universe, 3 decades ago.
What is the new air speed velocity of an unladen cliff swallow?
The article says it's because they are more maneuverable, but what if they just sit on their asses a lot unlike their easier flying longer winged relatives? Fly less, get hit less.
From http://en.wikipedia.org/wiki/Evolution:
Evolution by natural selection is a process that is inferred from three facts about populations:
1) more offspring are produced than can possibly survive
2) traits vary among individuals, leading to different rates of survival and reproduction
3) trait differences are heritable.
I was driving up in the mountains a year or so ago and saw a chipmunk run out into the road between me and the car coming the other way. Now normally this is pretty much certain doom for the chipmunk, but this one stopped calmly on the yellow line, stood up and waited for us to pass before continuing. I've always wondered if the evolutionary pressure of traffic combined with their short generation cycles would lead to critters less likely to become roadkill. Guess I have my answer.
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
The definition of evolution existed for over century before genetic material was discovered.
Keep changing the goalpost because the facts don't match your dogma, kinda like "climate change"
Yes, this may be due to evolution, not of the birds, but the automobile.
To generate increased fuel economy, today's automobile is a lot more streamlined than ones of the past. So there is less air disturbance. It may be that the birds with smaller wings are not affected by the turbulence as much as the larger winged birds are now, and can thus survive an encounter, whereas in the past, there was enough turbulence to affect the birds regardless of wingspan. Also, changes in traffic patterns and vehicle types changes the exhaust, which changes the local plant life, which changes the insect life, which ultimately changes the birds.
While it is simple to observe that long winged birds are being disproportionately killed and that the population's wingspan is growing shorter, and conclude that some sort of selection (Is it natural selection when birds are hit by cars?) is taking place, the reality may be quite different.
When our name is on the back of your car, we're behind you all the way!
Fly with a purpose when needed, live. Play dodge the highway traffic because you can, splat. If it takes more effort to fly then maybe you cut down on your recreational flying. Sort of like higher gas prices.
I had to go through a set of lights by a couple truck stops back in the day more than once a week. I noticed grackles (crowish kinda birds) that would wait on the posts or nearby for the lights to turn red. Then they would jump down and pick the grasshoppers and bugs out of the 18 wheeler grills. When the light turned green, they all flew back up and waited. They were quite well fed.
Is that seriously enough time for such an evolution to take place? I was not aware evolution happened so quickly, even accounting for their quicker viability for reproduction. Seems like there might be a million other reasons why this is happening, not because of something so recent.
What happened then was hilarious. The hare saw the left head light, became scared and jumped to the right. Being now closer to the right head light, it became scared again and jumped to the left. Then again to the right, and so the hare became trapped between her head lights. This continued until the next village where there was light all over the place, and the hare got away (... while the village people shook their head how anybody could let a perfectly good hare run away after having had such an easy opportunity for miles...)
Fast forward 35 years later. I was also driving on a nightly country road, and you guessed it a hare. Not knowing how to dress one either (and not being that fond of venison anyways), I just followed it for 2-3 jumps, then briefly switched off my lights to let it go...
So, apparently hares didn't evolve in those 35 years...
Are the short-winged swallows unable to mate with other swallow in their parent population?
This normally happens only if the two strains of livings are separated and allowed to develop independently. And even then it doesn't necessarily mean that the now occuring species can't interbred anymore. Polar bear and grizzly are a wellknown example of two species who could interbred, but normally don't do because they live in different environments. In this case, we talk about geographical species.
What we see here, is a so called genetic drift. While still being the same species, the average genotype is moved to shorter wings.
Has anyone, however, observed this selection effect going on for a long enough time for the emergence of new species?
Yes, there was an experiment with strains of E. coli (a type of bacteria), which were fed citric acid additionally to their normal diet. E. coli normally doesn't metabolize citric acid. But after about 12,000 generations, there was a new strain of E. coli which could metabolize citric acid. Bacteria don't interbred at all, they reproduce by cell division. Thus a definition of a species via cross-breeding doesn't make sense. E. coli is differentiated from other similar bacteria strains by not digesting citric acid. Thus, this new strain of citric acid digesting E. coli is a new bacteria species.
I'd say that the Book of Genesis was part of Christian tradition, and that explicitly states that God created animals and man from scratch, in direct contradiction to the Theory of Evolution.
What Bible are you reading? From Genesis 1:
11 And God said, Let the earth bring forth grass, the herb yielding seed, and the fruit tree yielding fruit after his kind, whose seed is in itself, upon the earth: and it was so.
12 And the earth abrought forth grass, and herb yielding seed after his kind, and the tree yielding fruit, whose seed was in itself, after his kind: and God saw that it was good.
I'm missing the part where it "explicitly" says "from scratch with no evolution involved." It just says God said, "Make it so," all Captain Picard like, and then it was carried out through some unspecified agency.There are literally no details about how it was done. Likewise with the animals:
20 And God said, Let the waters bring forth abundantly the moving creature that hath life, and fowl that may fly above the earth in the open firmament of heaven.
21 And God created great whales, and every living creature that moveth, which the waters brought forth abundantly, after their kind, and every winged fowl after his kind: and God saw that it was good.
22 And God blessed them, saying, Be fruitful, and multiply, and fill the waters in the seas, and let fowl multiply in the earth.
23 And the evening and the morning were the fifth day.
24 And God said, Let the earth bring forth the living creature after his kind, cattle, and creeping thing, and beast of the earth after his kind: and it was so.
25 And God made the beast of the earth after his kind, and cattle after their kind, and every thing that creepeth upon the earth after his kind: and God saw that it was good.
Even the word "day" could better be rendered "time period." A "day" might be 1 billion years. In any case, evolutionary theory neither proves nor disproves God. In fact, if you read Origin of Species, you'll find that Charles Darwin was not the atheist demigod smarmy atheists like to make him out to be. He speaks quite openly about God and pontificates that "Hey, maybe this is how God speciates animals." (Also, he wasn't particularly concerned with the ultimate origin of life. He was specifically concerned with speciation.)
Today's Sesame Street was brought to you by the number e.
A "day" might be 1 billion years.
And "seed" might be asteroids, "fowl" might be spaceships, "creeping thing" might be nanotech bots and "blessed" may be "provided a 1 billion year support contract". If you like to provide your own translation of every word and concept in the Bible, you can make it anything you want it to be, prove anything you like and be infinitely update-able.
If we were to accept this, it must be very comforting that Genesis can seem to be more than simplistic myth. But it doesn't stop it being fiction.
I'm pretty sure any non-idiotic *anybody* simply says the Bible is a collection of stories and parables with valuable life lessons for the place and time in which it was written. As with all old stories, they're usually rooted in some factual event that occurred at the time. Christians take it a step further claiming its writing was guided by God. Idiotic Christians take it even one step further claiming every word as a literal truth, but luckily there are very few of those.
I know it's fashionable to assume everybody who believes in Christianity takes every kernel of the Bible as an absolute truth, but most take the book as a whole. You talk about ignoring the details - with all of our modern science, we *still* can't grasp the details of how the universe was created.
Hell, I'm not even a Christian. Why do you jump to inflammatory conclusions and make me take their side?
+1 Disagree
Has anyone seen mutations arise that weren't in the gene pool of an organism and seen the mutated form "take over" a population because the mutation conferred a survival advantage
I saw a documentary recently that said there are nurse sharks near the bikini atoll that are believed to have developed a mutation (missing second dorsal fin) due to exposure to radiation from nuclear testing in the late 40's, early 50's. Normally that type of mutation only affects one or two generations, but the mutation has persisted to this day. I don't think anyone has theorized an advantage yet. They didn't detect any abnormal radiation levels in the water at this time.
YOU are the one providing an incorrect translation, you are the one insisting it means what you want it to mean.
The Hebrew word "yom" means "period of time". It may be used to mean 12 hours, may be used to mean 24 hours, and it may be used longer periods of time. For example Genesis 4:3: "And in process of time(yom) it came to pass, that Cain brought of the fruit of the ground an offering unto the Lord." In that case "yom" means "one growing season". That is a several month period of time.
To quote Lewis Black:
He believes that the earth was created in seven days. Whew! Takes my breath away. And why does he believe that? Because he read it in the Old Testament, which is the book of my people - the Jewish people. And that book wasn't good enough for you Christians, was it? You went, "No, we've got a better book, with a better character, you're going to LOVE him!" And you called your book NEW, and said our book was OLD!
And yet every Sunday I turn on the television set, and there's a priest or a pastor reading from my book, and interpreting it, and their interpretations, I have to tell you, are usually wrong. It's not their fault, because it's not their book. You never see a rabbi on the TV interpreting the New Testament, do you? If you want to truly understand the Old Testament, if there is something you don't quite get, there are Jews who walk among you, and THEY - I promise you this - will take TIME out of their VERY JEWY, JEWY DAY, and interpret for you anything that you're having trouble understanding. And we will do that, if, of course, the price is right.
The next time you want to argue Old Testament translation and interpretation, try asking someone who speaks the language. I don't claim to be fluent in the Hebrew, but I rather suspect I've spent more time in Hebrew School than you have.
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I have huge respect for a bird that can dive at 40 miles an hour to snatch a fly two inches off the ground without going 'splat'.
"Think about how stupid the average person is. Now, realise that half of them are dumber than that." - George Carlin