National Geographic News
Adelie penguin, Pygoscelis adeliae, flapping wings.

An Adélie penguin flaps its wings, which help the bird to swim.

Photograph by John Eastcott and Yva Momatiuk, National Geographic

Brian Handwerk

for National Geographic

Published May 20, 2013

Penguins lost the ability to fly eons ago, and scientists may have finally figured out why. A new study suggests that getting off the ground eventually just took too much effort for birds that were becoming expert swimmers.

Flight might make some aspects of penguins' Antarctic life much easier. The grueling march of the emperor penguins, for example, might take only a few easy hours rather than many deadly days. Escaping predators like leopard seals at the water's edge would also be easier if penguins could take flight, so scientists have often wondered why and how the birds lost that ability.

A popular theory of biomechanics suggests that the birds' once-flight-adapted wings simply became more and more efficient for swimming and eventually lost their ability to get penguins off the ground.

More efficient diving, on the other hand, increased the opportunities to forage for food at depth. A modern emperor penguin can hold its breath for more than 20 minutes and quickly dive to 1,500 feet (450 meters) to feast. (Related: "First Human Contact With Large Emperor Penguin Colony.")

The new study of energy costs in living birds that both fly and dive provides critical evidence to back up this theory.

"Clearly, form constrains function in wild animals, and movement in one medium creates tradeoffs with movement in a second medium," study co-author Kyle Elliott, of the University of Manitoba, said in a statement.

"Bottom line is that good flippers don't fly very well." (Related: "Giant Prehistoric Penguins Revealed: Big But Skinny.")

Sit, Swim, and Fly

The thick-billed murre or Brünnich's guillemot (Uria lomvia) uses its wings for diving much like penguins, but it also flies. Scientists theorized that its physiology and energy use may closely resemble those of the last flying penguin ancestors.

Other swimming birds, pelagic cormorants (Phalacrocorax pelagicus), propel themselves through the water with their feet. Elliott and colleagues assert that these birds can be considered biomechanical models for the lifestyle energy use of an ancient penguin ancestor that was the last of its line to take flight.

The thorough technical and isotope analysis of how guillemots burn energy reveals why today's penguins are grounded. Guillemots dive more efficiently than any other flying bird and are bested in diving only by penguins themselves, according to the study.

Flight, however, costs them more energy than any other known bird or vertebrate and has become difficult to maintain.

The team examined thick-billed murres at a colony in Nunavut, Canada, and pelagic cormorants at Middleton Island, Alaska. They injected the birds with stable isotopes of oxygen and hydrogen to serve as tracers to mark the physical costs of their activities. The team also fitted them with time-budget devices that track those activities—recording movements, speeds, and other data much like pedometers do.

"Basically the birds do only three things: sit, swim, and fly. So by measuring lots of birds and combining their time budgets with the total costs of living from the isotope measures, it is possible to calculate how much each component of the budget costs," explained study co-author John Speakman, who leads the Energetics Research Group at the University of Aberdeen, Scotland.

"The assumption is that [penguins] evolved from an auk-like ancestor," Speakman continued.

"This would involve a progressive reduction in wing size, which makes diving more efficient and flying less so. Penguin bones also thickened over the ages, as lighter bones that make it easier for birds to fly gave way to more dense bones, which may have helped make them less buoyant for diving." But Speakman believes the wing changes were the primary adaptation.

Elegant Explanation

"These results make a lot of sense," said University of Texas at Austin's Julia Clarke, who studies bird evolution and how the flight stroke was co-opted for underwater diving.

"There have been different scenarios explored for the origin of penguins but little relevant data. These new findings from other diving birds like murres provide an elegant explanation of a key step in the wing-to-flipper transition."

Katsufumi Sato, a behavioral ecologist at the University of Tokyo's Ocean Research Institute and a National Geographic Society Emerging Explorer, added that the work indicates an important reason why penguins stopped flying and evolved larger body sizes—they needed an edge in the water.

"An interesting example is the little penguin, which is smaller than some Alcidae [a family of birds]," and weighs only about two pounds (one kilogram), said Sato. "[The] dive cost of the murre is similar to that of the little penguin, which means little penguins cannot survive against the murre, which can dive and fly."

Bigger bodies boost dive efficiency and allow for longer dives, which may be why rapid evolution produced so many bigger-bodied penguins soon after the animals lost the ability to fly.

Penguins Grounded by Taste for Fish?

Comparing multiple species, in the way this study does, points to a compelling pattern, said Chris Thaxter, a seabird ecologist with the British Trust for Ornithology.

"When wings are used both above and below water, there may be an evolutionary tipping point beyond which flight is too costly and unsustainable." Clarke, Sato, and Thaxter were not involved in the study, which was published in the May 20 edition of the journal Proceedings of the National Academy of Sciences.

Scientists don't have fossils of flighted penguin ancestors, and the earliest known penguin dates to just after the Cretaceous-Tertiary boundary (58 to 60 million years ago).

"It is tempting to speculate that the evolution of penguins happened in that explosive radiation [of mammal species] that happened just after the K-T event," when many species went extinct, Speakman said. "However, there is no direct evidence to support this, and it could have happened any time during the late Cretaceous."

In nature such adaptations happen for good reason, typically related to survival and reproduction. So a convincing case might be made for why penguins would have given up flight while taking to the seas.

"What we do know is that in the radiation of the mammals after the K-T event, there suddenly [in geological terms] appear a whole load of mammals that would have been serious competitors for aquatic resources [like] cetaceans and pinnipeds," Speakman said.

"So this new competitive environment may have placed a greater benefit on being more efficient swimmers and divers for aquatic seabirds. That push toward being more efficient in the aquatic environment may have been enough to tip them over the edge into flightlessness."

Jonny O
Jonny O

I'll tell you why: because they never could. Penguins most likely started off as ground-bound birds, or semi-flying birds like chickens. Prior to the evolution of marine mammals, they specialized and acquired their swimming and diving abilities. Once the mammals entered the same environmental niche, the penguins were held in check - becoming the hunted instead of just the hunter. Antarctica has long been their sanctuary because of the absence of any ground-bound predators.

Lungit Zarista
Lungit Zarista

Being able or disable to fly, they still cute enough for me.hahahaha :D

Christian Duerig
Christian Duerig

The K-T event has a new name: C-P event, because the Term "Tertinary " has been replaced by: Neogene and Paleogene. The K stands for the german word "Kreide" which is "Cretaceous" in english. You can persuade yourself with the "2012 Geological Time Scale".

C-P means Cretaceous-Paleogene. 

K-T meant Kreide-Tertiär.

The rest of this article is reasonable speculation.

jim adams
jim adams

I note you say that penguins started -- as a group of dinosaur descendants -- somewhen in the region of the KT boundary, back when Antarctica was a coniferous forest,  or at least had a wide border around Antarctica.

1) Evolution works more rapidly in small populations than in large populations which is why many new species appear rapidly after a wide-spread disaster like the KT cataclysm, and slowly during stable periods when our world filled to carrying capacity with many species. Prior to the 1600s, our world was stable climatically and mostly filled to carrying capacity with mature ecosystems (see Paradise Found by Steve Nicholls). 

2)Birds, including penguins behave instinctively far more than we humans.  Many species of birds migrate from Place A to B, going to the appropriate places for their species without mom and dad showing them the way (cf humming birds where the young may leave for the sunny south as much as a month later than the older birds). Instincts are not something birds think about and then decide. It is a driven imperative.It sounds like the Emperor Penguin long march may be an instinctive adaptation made when the climate was much different.

Ina Bliss
Ina Bliss

All Animals (animated symbols), also as in insects, fish, birds, including Penguins, are precisely and perfectly specialized for and suited to their environments, making "EVOLUTION" unnecessary - and simplicity, as in genius, is optimum necessity(!), including symmetry, are only achievable by design.

God is not religious. He is absolute in that every single iota of His universe (ONE verse) exists only once: Every specimen (variation, variety and version) is unique and no leaf, scale, snowflake, scenario, snapshot or thought-impulse repeats itself, thereby proving His awesomeness, might, precision, simultaneous presence of zillions of SAM (simultaneously -not "randomly"- accessible memory) and love for His perfect creation.

"Scientists", having thrown all logic, consistency and in-context thinking out of the window in their rebellion against being mere small, relative, symbolic 2D photographs of The Absolute One (Sh'ma), their All-in-one Animator,  called God, Owner and Operator of the cosmos, breathing the very air that symbolizes Invisible Spirit, then immediately forgetting it exists and considering themselves "separate" from all else, are like saltwater drops about to seep into the sand, trying to "dissect" the immeasurable, declaring the nearby ocean "non-existent", thinking they live on a spinning ball (balls of any size HAVE NO horizon) etc pp --->Ignorance is the transgression that still kills them on the eternal Sabbath Day, rung in by Jesus The Christ, the only man according to the heavenly blue-print for man and only one to point the way as to "How To Overcome Death", the purpose for our physical existence.

Mason Hein
Mason Hein

"Scientists don't have fossils of flighted penguin ancestors..."

That's because there aren't any. Just like a 1984 Ford Escort didn't rust, freeze, get struck by lightning, and suddenly evolve into a 1985 Ford Escort. 

For NatGeo to perpetuate the theory of Genesis by Macro-Evolution is unconscionable in this day and age. It flies in the face of everything we have learned about living organisms over the last 150 years.

In Darwin's day, researchers looked at cells under the microscope and saw little balloons filled with goo they called protoplasm, so they thought cells were simple forms of life. 150 years later, we know that there are many types of cells, and everything about a cell is stunningly complex.

The smallest known genome (Mycoplasma genitalium) has 482 genes. The minimum possible for an organism to survive is probably 200 to 300 genes.  Most bacteria have 1000 to 4000 genes.  The human body has about 210 different types of cells. That's an awful lot of random chances.

Cells are made of proteins, and everything that goes on in a creature involves proteins interacting with each other.  Proteins are generally 50 to 2000 amino acids long; a typical one has about 300 amino acids.  Ribosomes are molecular machines that build proteins in cells, using messenger RNA as the template. They are amazingly complex. Scientists still haven't fully unlocked the mechanisms behind how they know which proteins to produce at any given time.

The odds of random events causing even a single functional cell to form from inanimate matter is beyond calculation. Science is growing ever closer to unlocking the "firmware" that resides in living cells, but they are no closer to creating them by random action than they were in 1850. 

The reason that there are such things as species and missing links is that those are the earmarks of a creationary process... where you build off an early design, and create something similar but different (or better). But, it doesn't just magically morph from one to the other without intervention.

Bear in mind... this isn't a religious rant. I'm not suggesting I know the nature of our origin. However, it should be blindingly obvious that there's too much complexity and balance in living matter for random action to have generated it. There is a deliberate intelligent design behind our origin... and it's a shame that NatGeo doesn't have the courage to tell that story instead of this work of fiction.

Joseph Bandana
Joseph Bandana

Penguins are just another example of creation misseps....creating a bird that chooses not to fly! hehehe!! Penguins were tempted by Satan to eat fishies while gods had created Penguins to eat mosquitoes for Mankind. Thanks, Satan! (and pass the Deet..) Of course we are all-too familiar with the creation misstake of foreskins on the malechild. This mistake is easily correctable by circumcism (cutting off that offending skin from the newborn babyboi..which is ordered by the gods in that HolyMolyBibleBook. Notice the HMBB does not order Female circumcism, which is a clear indication there is no creation mistake there! Yeah, all the answers are right there in that BibleBook if you will only Trustie. Even has instructions about Internet copywright and tax laws if you have faith to read Leviticus.If you accept this teaching...there is a Mansion awaiting yew on GoldStreetsHeaven!! Really!! (ohyeah........but..........yewgottadiefirst.............................sosorryaboutthat!)

donnie rose
donnie rose

Wrong wrong wrong, we all know penguins are the spawn of satan and god cursed them to never fly!!!!(inevitably someone will think I am clarify  I am not)

Rolf Hawkins
Rolf Hawkins

I'm sorry, but this seems incredibly obvious even to the meanest of intelligences. And, speaking of mean intelligences, my own is trying to determine what the net benefit is to anyone inside or outside of the academic circles now that this finding has been published. Years of research and hypothesizing, debate, further study, arguments, rude words and eventual conclusions have established what we already knew: that penguins rock at swimming in the water as opposed to the air, because that's where a plentiful supply of fish can be found, and the simple fact that the bird feeders on my deck are not only 20 feet off the ground, but 10,000+ miles away.

Rodolfo Duriez
Rodolfo Duriez

@Ina Bliss Gawd, go read a couple of books. Your argument was attempted in the times of Darwin, and even GOD LOVING Victorians agreed that it lacked both logic and evidence.

Do your self a service, and stop blabbering. It is embarrassing to read.

Joseph Bandana
Joseph Bandana

@Ina Bliss sorry about those MeanRomanSoldiers and what they did to your god! Anyhow, your god raised from the deadzone like the first XtianRobZombie just 2 days later on Sunday AM, so....even though he cannot be the Messiah who must raise from the Deadzone on the 3rd day, at least he did raise like a loaf of bread! And that is a pretty decent cheap pet trick on par with walkonwater!!

Joseph Bandana
Joseph Bandana

@Ina Bliss do you explain perfectly created creatures which became extinct? Or....are dinosaurs still alive in Tibet?!! hehehe!! Why did your perfectly wonderful gods created so many imperfect creatures like....well...YOU?!!! HAHAHAHAHA!!! (takethat....superstition!!)

Philly Jimi
Philly Jimi

@Mason Hein Wrong your babble is a religious rant.  This is just the standard ID 101 cut and paste, argument from ignorance.  

You don't bother to learn the science and you make it sound really complex (which it is) thus it sounds impossible therefore a magic zombie's daddy created it all in 7 days because an old story book said so.  

Mikel Moore
Mikel Moore

@Mason Hein Funny, when I trace the organization'a materials, it goes straight to the Discovery Institute, the Intelligent Design people who promoted not teaching evolution and lost their case before the Christian, conservative GW Bush appointed judge who stated that this viewpoint was not supportable as science, but was a religious perspective and banned its materials being used as science in Dover, PA.  

jack london
jack london

@Mason Hein   Evolution is not a theory.  Evolution is a many times scientifically proven fact.   Creationism has no science or proof.  

Read Isaac Asimov, Steven Hawkins.

"The word God is for me nothing more than the expression and product of human weaknesses, the Bible a collection of honorable, but still primitive legends which are nevertheless pretty childish. No interpretation, no matter how subtle, can (for me) change this," wrote Einstein, who won the Nobel Prize in Physics in 1921.

C. Dufour
C. Dufour

@Mason Hein "That's because there aren't any. Just like a 1984 Ford Escort didn't rust, freeze, get struck by lightning, and suddenly evolve into a 1985 Ford Escort. "

thats not quite how evolution, see evolution acts on a population in between generations, not on individuals.  Therefore as a population of 1984 fords is faced by natural selection (or in this case human selection for the more desired traits) the next generations will gradually become the 1985 model. 

Of course Cars are not animals so they are a poor example for evolution.

Mason Hein
Mason Hein

What science are you talking about?

Point out the science! 

Find me a single documented case!  Just one... 

That shouldn't be so hard, should it?

Science is based on FACTS.

Find me a single case that demonstrates how your so-called "science" works.

Provide me just one documented case which has demonstrated how amino acids have been formed into single cells.

If you can do that, then I'll delete every post I've made here, and admit you were right.

I'll be waiting.

Mason Hein
Mason Hein

@Mikel Moore So, you don't personally have any issue with the points that I raise in my 4 posts here? Excellent! I'm glad I was able to get my message across in a clear and coherent manner.

It's a shame that the judge in question didn't see that inter species evolution and genesis via evolution are also (at present) completely unsupportable by science.

Considering macro-evolution's popularity despite the utter lack of of scientific proof or clinical trials that demonstrate it's method, one might consider that macro-evolution is a religion itself.

Who says scientific study doesn't have inertia? (lol)

Mason Hein
Mason Hein

In addition, study on mutations have shown that approximately 70 percent of genome mutations have damaging effects, with the remaining 30 percent being either neutral or weakly beneficial.

The idea of a higher complexity organism being generated automatically through random action from a lower complexity organism even over tens of thousands of generations is mathematically unsound.

If you're going to rely on billions of random chances going together the right way, you'd hope your new creature wouldn't have a 7 in 10 chance of killing itself with a secondary mutation on one of the many changes somewhere along the chain.

Mason Hein
Mason Hein

Mutation is just an extreme case of variation, where the genome sequence itself is altered. However, even over time, and multiple mutations, mutation has never been shown as a tenable means of changing one species into another.

Bacteria remain bacteria despite mutations.

Mason Hein
Mason Hein

@jack london I did not mention God, or the Bible. Please stop bringing these into a discussion where they have no place.

If you are smart enough to read Asimov, Hawking, and Einstein, you should have no problem following this logic.

You have made a common mistake. You have confused evolutional variation (micro-evolution) with inter-species evolution and genesis by evolution (macro-evolution).

There is no doubt that evolution is a scientifically proven fact. Living organisms DO indeed evolve over time. They adapt and change in response to many external stimuli, such as diet, environment, and interactions with other organisms. This has been documented and proven over and over. I do not question this in the least.

However, what has never been proven is inter-species variation or genesis by evolution. These also have no science or proof, but are nothing more than theories which have never been duplicated in a lab, or documented in nature. Never. This, despite more than a hundred years of study, and countless projects to TRY to prove them.

You see, there are strict limits to evolutional variation which are never crossed, something which every breeder of animals or plants is aware of.  Whenever variation is pushed to extremes by selective breeding (to get the most milk from cows, sugar from beets, bristles on fruit flies, or any other characteristic), the line becomes sterile and dies out. The very nature of cells prohibit change beyond that limit, which has been proven in the lab with bacteria. You see, bacteria never evolve into anything other than bacteria even over tens of thousands of generations.

In addition, living organisms have immune systems which attack and prevent changes beyond certain given limitations. This is coded into the very fabric of the cells themselves. The only non-vario-genetic modifications observed and documented to date involve defects which shorten the effectiveness or life of the organism. 

The bottom line is that there are boundaries which cannot be crossed through random natural action, even when given billions and billions of chances.

Finally, the weakest link in the chain is the theory that life spontaneously generated from inorganic matter. Even the simplest cell contains BILLIONS of base-pairs of nucleotides in DNA, working with RNA to transfer the patterns of proteins from itself to the ribosomes through processes so complex that even our finest scientists today have not fully defined them. 

Rolling a four sided die (ATGC), and getting the exact billion character long sequence to come up properly might be arguably possible given infinite chances. However, that would only be one of the stands you'd need out of hundreds or even thousands. For this to happen, the entire universe would have to be completely full of organic goo of all the failed attempts. (To have a billion chances at something, you must have a billion results, correct?) Yet, this is NOT what we see here on Earth. 

If inter-species evolution was real, then the nature of life on this planet would not exist as we see it. Instead of definable species, we would CURRENTLY see one unbroken sustainable life-chain from amino acid to single-celled creatures, branching off to all the most modern tips of the evolutionary tree. We would have already documented at least one case of inter-species migration. We would have been able to synthesize a new organism (or at least a cell) from random action of amino acids in a controlled lab environment. Not only hasn't science done these things, they have detected boundaries, processes,  and limits which prevent this. It's not a simple goo which exists in a cell, but a stunningly complex machine. 

The mathematical odds of random action generating life as we currently understand it is impossible. Plain and simple.

I'm not alone in this way of thinking... consider the names on the list in this link, and their statement:

Remember, I'm not talking religion here... I'm talking science. Please stick to the talking points at hand.

Joseph Bandana
Joseph Bandana

@jack london Er....not always honorable...LoL!! Incest, murder, adultery, genocide; and these are the convicted crimes of those who are the god's specialchosen heros of that holymolybiblebook!! Is so funney in our 21st century our Western World mostly believes in Jesus walks on water and changes water to wine is a BigDeal!! What about Jets, and Computers, and Cars and I-phones!!! Now....Those are Miracles!! Jesus just did cheappettricks!! (sorryjesus...youdidthebestyoucould2000yearsago!)

Mason Hein
Mason Hein

You did not address a single point I made, and insist on talking about religion, faith, and God. You then change the topic.

Try this... read my posts, and answer my question.

Find a single case where scientists have demonstrated the spontaneous creation of a single cell (or any of it's major components) through random action.

Philly Jimi
Philly Jimi

@Mason Hein Only a religious person would suggest that macro-evolution is a religion itself.  You're world view is religious based which is faith based by definition thus you assume everything is taken on some type of faith.  

Well here is one for you, child cancers the black death.  If there is a designer who created and designed all of this.  He is one really evil and sick being for creating such monsters.   

You have to admit the designer doesn't love us and doesn't think were special.  I won't even get into the bad designs he used in creating us.  You know like mixing the food digestion and air breathing plumbing together so choking to death is rather common.  

Maybe if you ever find out who this designer is we can sue him for the most awful crimes against humanity and all the species of our planet.  This designer is the most evil being ever, there is no argument against that.  

Mason Hein
Mason Hein

At no point did I ever say that new species could form in one generation. The fact that you would even state something so preposterous is mind-boggling.

In truth, I'm actually proposing that new species CANNOT FORM AT ALL from other species. 

Fact: Any time variation (micro-evolution) is pushed too far, then the organism becomes sterile. Sterile means that the mutated organism cannot reproduce. If the mutated organism cannot reproduce, then the variation or mutation in question is NOT passed along to future generations.

Fact: Science has never shown the mechanism for how one species can evolve into another. They have a theory, yes... but they have nothing else.

Claiming that variation (micro-evolution) can create life from inorganic matter, or mutate organisms (over many generations) into another species is like demonstrating that you can gain altitude by climbing two steps on a stepladder (true), and then claiming that you could walk to the moon on a ladder (fallacy).

Philly Jimi
Philly Jimi

@Mason Hein New species don't form in 1 generation.  You don't understand evolution.  You don't understand the most basic high school definition of what evolution is.  The idea that you think evolution says new species magically form in 1 generation is mind boggling.  

Mason Hein
Mason Hein

Ignorance?   Hardly. 

Please offer a reference to any documented case where scientists have demonstrated that they can create DNA, RNA, or Ribosomes in the lab through random action.

You won't be able to, because it has never been done.

You're the religious one. A system of beliefs based on faith without proofs is Religion... and that's what you're supporting here. I didn't mention God. You did. 

Philly Jimi
Philly Jimi

@Mason Hein Wrong you're talking about religion.  

You're making one giant argument from ignorance.  

The fact that you stated ..."However, what has never been proven is inter-species variation or genesis by evolution. These also have no science or proof, but are nothing more than theories which have never been duplicated in a lab, or documented in nature. Never. This, despite more than a hundred years of study, and countless projects to TRY to prove them."...

...only proves you have no idea of what evolution is.  

Again your argument is a religious argument.  Pretend all you want your sales pitch is for a designer and the designer is your particular god.  Remember bearing false witness is a big no no.   

Crystal Eyes
Crystal Eyes

@Joseph Bandana @jack london 

That is beacause we have a choice, choice to do right or wrong. We are not robots. So if God created men to be always obey, then we are just like robot


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