Anyway, two related links this week about bird/dinosaur evolution.
Xiaotingia zhengi
Earliest Bird was Not a Bird? New Fossil Muddles the Archaeopteryx Story
A new discovery of a fossil which sits somewhere between feathered dinosaur/early bird has changed the position of Archaeopteryx from the earliest bird to more of a distant bird cousin, or maybe just a dinosaur with feathers that watched the birds evolve. Adding this new fossil to the evolutionary tree moves Archaeopteryx out of the bird lineage and into a group of dinosaurs along with the new discovery named Xiaotingia zhengi.
Most importantly, this new discovery illustrates an extremely basic and important aspect of science which is often lost in public education. Science is an ever-changing, fluid entity. Just because Archaeopteryx has been moved from the position of earliest bird, does not mean it is gone, or not an important fossil. And it certainly doesn't mean that evolution is wrong. Science is about putting forth hypotheses, and seeing if the data support them. If the data do not, they are discarded or revised. It is not correct to say that these hypotheses were "wrong." They simply reflected an earlier set of data. Science is full of examples of this.
49 comments:
I just read a comment on a different related blog article - 'First Pluto and now Archaeopteryx! Science is ruining my childhood!" :)
What I essentially got from both of these articles was an appreciation of scientific advancements. As more evidence accumulates, scientific finding become more and more certain. Theories (such as the Archeopteryx being the earliest bird) that have withstood several decades of study may undergo refinement of detail, but are not necessarily being overturned completely.
Science is evaluating which theory best fits the data available, and as more date becomes available, another theory may seem to fit better. Believing something that has no mechanism for change is just silly.
Reading the original paper by Xu helped clear up some of my initial confusion. Basically, features that were characteristic of birds are now thought to be characteristic of Paraves in general (comprising of the Avialae, including Archaeopteryx and modern birds, and the Deinonychosauria). Xu's analysis suggests that Archaeopteryx may not be central in the transition to modern birds.
I'd be interested in seeing further research done to validate Xu's findings. And perhaps he may be 'more right' - but only according to the data that was available to him. Let's say that Xu's theory is confirmed and accepted. I'm certain that it will be challenged, just as it is challenging Archaeopteryx today. Because as Dr. H pointed out, science is ever-changing.
To be honest, I found these two articles a tad confusing. Not to say I didn't understand the general concept of them but it was hard to analyze the itty-bitty pieces of them. Anyway, once I realized the central Idea I was able to formulate somewhat of an opinion on how I felt about these articles. For the first article, it mentions the Xiaotengia Zhengi which is a new specimen found. This specimen has a close resemblance to the archaeopteryx. Paleontologists are astounded by this because at first they had thought that the archaeopteryx was a distant relative to modern birds. However, it's linking with the newly found Xiaotengia are leading scientists to believe that both of those species may have to be put in an entirely new classification altogether. This new classification also presents evidence of a bigger gap in earlier bird history which leaves so much more discovering too. Also, since Xiatengia and Archaeopteryx are carnivorous, this leaves speculation that modern birds are descended from herbivorous ancestors due to their current diet.
In the second article, it merely backs up the first article. Basically, it states that all primitive birds were herbivorous where as Xiaotengi and Archaeopteryx were carnivorous. This further distances them from modern bird species. It also states that the Evolutionary route from dinosaurs to bird was a long and it wasn't quite "linear" either.
In reality, the discovery of this new species has resulted in far more possibilities and open slots in the evolutionary tree for modern birds. The new finding has also sparked new ideas in scientists as theories are beginning to pour in from the minds of many intelligent researchers who are on the quest to find out their evolutionary origin. As time progresses, I believe we will find out a huge amount about this ancient history and hopefully it is soon.
Amazing how one discovery can really mess with the order of an evolutionary model. However, it’s understandable because researchers even today are still uncovering new species that fill in evolutionary holes, which in result can send previous links haywire. In the first article, PZ Myers states that incorporating the Xiaotingia zhengi into the pre existing model (with Archaeopteryx as a very close cousin to the modern bird) pulled Archaeopteryx from its position into a group that displays it as a more distant cousin to the modern bird than previously thought. It makes more sense though, as the caption of the chart explains that Archaeopteryx’s build hinted at a carnivorous diet while most modern birds (evolved from “bird-like” dinosaurs) are herbivores.
Ed Yong’s article further elaborates on the changes brought by the discovery of the Xiaotingia zhengi. He says, “Archaeopteryx is widely heralded as the first bird, occupying a pivotal position in the origins of this group.” Obviously, a change at the base of the model causes a chain reaction in more recent branches-that’s why the discovery of Xiaotingia zhengi is so remarkable. Not only does it displace what researchers previously thought of the Archaeopteryx’s relation to the modern bird, but it also catalyzes a flurry of questions that challenges the understanding they had of the bird group, “Archaeopteryx’s position has been so sacrosanct that its body had guided many of our ideas about the origins of birds. It grounds our understanding of this group.” As Yong predicts, Creationists will pounce on this, using the inconsistencies as a vantage point to argue that the theory of evolution is discreditable, but he states in a pre emptive effort that weakness and inconsistency are to be expected as with all constantly shifting models. It's necessary that we keep moving with this process and maybe one day have a complete model of the dinosaur-bird evolutionary tree.
After reading both articles I can tell that the discovery of Xiaotingia is a very big one. It changed the way many people look at the evolutionary trail of birds. The reason that stood out the most to be was that Xiaotingia is an herbivore and Archaeopteryx is a carnivore. That shows that halfway through evolution birds didn’t switch to herbivores they were always herbivores to begin with. What these scientists are trying to do is no simple task, is not shocking that mistakes could be made down the line. After all they’re trying to put together the evolutionary tree of creatures that lived over 150 million years ago. I find it hard enough simply understanding how my family all fits together. And to make matters worse, that also have very limited information. It’s like trying to put together a puzzle missing half of its pieces. This is also a constant reminder that science is still growing and changing everyday and that we don’t already have all the answers.
After I read both of the articles I can understand how this discovery will change the way scientists look at the tree of life. It shows how one thing can change the way that everything else is looked at. Even though the Archaeopteryx has become less important in the evolution of birds, another find could take its place. It is interesting that because of this it may be discovered that birds are really descended from herbivores and did not in fact evolve due to the need to hunt. Maybe a species evolved to fly in order to reach the fruit it was too small to get to otherwise. No one can ever be one hundred percent sure of how animals came to be what they are today. Science is always changing the way we think about things and the discovery of the Xiaotingia is just another example of that.
When I think about science and all these recent discoveries, it really reminds all of us that nothing is ever set in stone. These articles serve as a reminder that new discoveries can continue to alter what we know today. The lineage of birds can't be determined fully by what is uncovered since there are many missing pieces that still need to be uncovered. The new discovery by Xu is enlightening since prior to the discovery we believed that Archaeopteryx was the basis for the evolution of birds. All these fossils are interconnected, despite the controversy the discovery creates. Just as the article states, the new discovery adds depth to the tree that modern birds originate from.
Many people might be open to the idea that the Xiaotingia could redefine the family tree, but there are many skeptics. There must be a multitude of unknown species in almost all animal families. Personally, I think that the discovery has enough support to prove that evolution truly occurs and that this species could have existed prior to that of the Archaeopteryx. It's nice to know that new advances can change the way we live and learn about life. It shows that we are able to improve our knowledge and that there's always something to be learned, especially in the realm of science.
I had a hard time understanding these articles. I think I have a general idea of what they are both talking about. The first article introduces the Xiaotingia zhengi, which is a new feathered dinosaur discovered in China. The Archaeopteryx was grouped together with the Xiaotingia zhengi, since they had similarities. They were more similar to each other than other avian varieties, which created a new classification for them. I think that as paleontologists discover new varieties of feathered dinosaurs, some might have to be put into entirely new classifications. Science is always changing. New things are being discovered all the time. That means our systems of classification must conform to these changes.
The 2nd article goes into more detail about why Archaeopteryx was classified with Xiaotingia zhengi. They were both classified with small predatory dinosaurs, which included Velociraptors. Archaeopteryx was sort of pushed to the side a little bit because some other dinosaurs were believed to be the earliest birds. However, this theory is weak and needs support.
Scientists have also unveiled new fossils of dinosaurs that are more closely related to modern birds than Archaeopteryx or are actually primitive birds themselves. All in all, scientists are starting to reshape the image of primitive birds. Scientists have always followed the Archaeopteryx model and thought other primitive birds to be similar to it. But that has now changed.
These two articles honestly confused me a bit, but I think I got the gist. Basically, it concerned a new fossil of a pigeon-like dromeosaur called a Xiaotingia. Apparently, its discovery removed Archaeopteryx, an animal that was thought to be one of the most primitive birds, from that status to that of a proto-bird, more aligned evolutionarily with dinosaurs. This is because the Xiaotingia’s data didn’t correlate much with birds. Since the Archaeopteryx shared more characteristics with it than other primitive Aves class creatures, scientists have recently classified them both as distant relatives to modern birds, instead of direct ancestors. This realization is important because it changed some of the previous ideas scientists held about early birds, such as skeletal composition and dietary habits. However, some scientists have claimed such evidence about the Archaeopteryx’s relation to the Xiaotingia is weak and that a new fossil could once again align Archaeopteryx as an ancient bird. This is a great example of how the field of science is always changing with the addition of new information.
I also found the comic thing to be funny, though it took me a moment to understand.
I believe that this blog post covers two important points. Not only does it announce an important discovery in the timeline of prehistoric evolution, but also touches upon the political aspect of science. Specifically, what happens when a grounded idea is called into question by a new credible discovery.
This discovery reminds me of another article I read regarding a debate on the nature of dinosaurs and their relation to modern mammals, specifically on whether or not dinosaurs were warm or cold blooded. Those who believed that dinosaurs were cold blooded point to the sheer size, thus homeostasis is difficult to maintain. However, this discovery linking the earliest birds to dinosaurs, in addition to analyzing isotopic concentrations in teeth of sauropods, who were one of the biggest land animals to have ever lived, indicate that they were warm blooded.
All this ties back into the idea that theories and hypothesis only reflect the extent of our current knowledge. And because our scientific knowledge increases exponentially, new theories are constantly being debunked and accepted. Luckily, the modern day scientific community seems open minded on most issues. But when an idea that has not only been around in terms of time, but also something from which other theories stem from is challenged, i.e the discovery of Xiaotingia, this understandably generates conflict.
This only highlights the importance of an open mind, constant debate, and tenacious experimentation and study.
To be candid, I had some trouble understanding the terminology and dynamic of these two articles. However, the overall picture seems pretty clear. Essentially, what these two articles are implying is that Palaeontologist, Xing Xu’s, discovery of fossils from the dromeosaur, Xiaotingia, may or may permanently replaced Archaeopleryx as being one of the most primordial of birds. Scientists classified both, Xiaotingia and Archaeoleryx, as being distant relatives to the modern bird, rather than direct ancestors. Xiaotingia’s findings just might alter the archaic family tree; however merely a new discovery of the skeletal remains can realign Archaeoplteryx back to its initial position. These findings are ultimately questioning the lineage of the modern birds.
I obviously do not understand the whole dynamic of the archaic family tree nor the complexity behind classifying fossils; however, even so, it is clear how science is evermore a fickle of information and speculations. Sometimes we become delusional, thinking that we have discovered all there is to be unveiled, however novel breakthroughs, as such, remind us of the fragility and capriciousness of science.
After reading both articles, I realize that the discovery of the new fossil, Xiaotingia zhengi, has changed scientists’ belief that Archaeopteryx was one of the earliest birds. When comparing Archaeopteryx, Xiaotingia zhengi, and modern birds, scientists discovered that Archaeopteryx was more closely related to deinonychosaurs, not the birds. The articles do mention, however, that there is not a lot of statistical evidence to support this idea, but it will be interesting to see how further research will support or refute this idea. The discovery of this new fossil will give scientists greater insight into early birds and how these birds evolved into the modern birds that are around today. One of the things I love most about science is that it is always changing and that there are new discoveries every day that shape our understanding of the world around us. I can not wait for future discoveries that will offer even more insight into the world’s earliest creatures.
I actually find dinosaurs and anything related to the Jurassic period to be extremely interesting. When I started to read the article, since the Archaeopteryx was from this time period, I was confused as to why it was considered as the earliest bird. Therefore, it should have been already classified as a dromeosaur and the discovery of the Xiaotingia should just confirm that fact, right?
Besides that, I'm excited to see what discoveries in the future will say about the evolution of birds and the confirmation of whether they were herbivores or carnivores. I wonder what new fossil finds, especially transitional fossils, will say about how birds came about or the sort.
Simply put, I believe this is what makes science and evolution so great. Although we find evidence that supports one way or another, we can never truly have a definite answer because science seems to constantly breakthrough our original discoveries.
After I read both the articles I realized how much one new discovery could change an entire family tree. I knew that birds descended from dinosaurs, but I didn't know which type of specific dinosaur. The article said that before the discovery of the new fossil, birds were known as the descendents of Archaeopteryx. These two articles proove that evolution is the reason behind all the species that live in today's society. One new discovery leads to another species that may have existed in the past. The fossil found in China is one step up in discovering what really existed in the time period before we came along. I am still amazed by the fact that one new fossil discovery could change an entire family tree.
After reading these articles I got a better understanding of how the realm of science is ever-changing. A recent discovery of the Xiaotingia zhengi fossil in China is the perfect example of this. After an analysis of the Xiaotingia specimen, scientists found that it had striking similarities with the Archaepteryx, which was considered the proto-bird on the bird family tree. However, the Archaepteryx no longer holds the position of the oldest bird ever since the discovery of Xiaotingia caused it to move into a new classification tree. This forces scientists into modifying their idea of primitive birds and how they have evolved since ancient times. Although it is an arduous task, I know that it will eventually sharpen our knowledge. I think it’s amazing how one discovery can make such a large impact on science as we know it. The more discoveries there are, the more science will continue to advance and expand our knowledge.
In the second article, Ed Yong mentions that all the reconstructions (whether or not the Archaepteryx is or isn't part of the bird family) are weak. Only with more time and advancements can we tell where everything belongs on the family trees. With every new discovery, the position of the Archaepteryx can change again. With all this uncertainty, Creationists will definitely attack the theory of evolution because of the gap created when the Archaepteryx was moved. However, I still believe that in time, the gap will be filled and that evolution is in fact a part of nature.
I also found these articles difficult to understand. However, reading these articles made me realize how interesting evolution is. Through it we can look at fossils to find out where we originated from and from whom. One small discovery could change scientists' view on where we came from.
The Archaeopteryx was originally believed to belong to the birds since the computer program told them to. I actually think they should not have relied on a computer to tell them where it came from. However, when scientists found the Xiaotingia zhengi fossil they were not so sure that the Archaeopteryx was considered to be a bird anymore.
When scientists examined the Xiaotingia zhengi fossil, many similarities were found between it and the Archaeopteryx. When the Xiaotingia information was plugged into the computer program it showed to be more of a dromeosaur rather than a bird. So scientists now question the path of where the Archaeopreryx came from. It turns out it is not a direct ancestor of the birds but more distant.
It is interesting how one discovery can alter scientists' opinions about anything. Once a new discovery is made, everything seems to change.
I personally find it really amazing how scientists are capable of discovering so much about extinct creatures through fossils and such. Although I do not fully understand exactly how they go about figuring out so much data, I still find it to be very fascinating. Even though it is very cool, I can't help but feel skeptical about the conclusions scientists are coming to. According to the article a scientist believes that he has disapproved someone else's theory about a certain extinct dinosaur. I feel skeptical about dinosaurs because I can't understand how scientists can be accurate about creatures that have been extinct for hundreds of years.
After reading both articles, I realized how just one discovery can change evolutionary model. The Archaeopteryx which was known to be one of the earliest birds was more closely related to the Xiaotengia Zhengi which is a newly discovered specimen. The Archaeopteryx was considered the proto-bird of the but after the Feathered-dinosaur, the Xiaotengia Zhengi was discovered the Archaeopteryx was put in a new classification all together. This helps modify the ideas of scientists that primitive birds have evolved from the ancient times. The 2nd article goes into more depth about why the Archaeopteryx is classified with the Xiaotengia Zhengi. The advancements in science can only tell us where everything is on the family tree of birds.
I feel that the two articles revolved around the idea that the Archaeopteryx should be directly removed from the immediate bird lineage and into its own due a newly found dinosaur, deemed Xiaotingia zhengi. Some say that such a change is unnecessary because the evidence is too weak, and others claim that it is a revolutionary discovery that could sharpen man's understanding of the mid-Jurassic age. Personally, I have no stance on this subject because I know nothing of dinosaurs. However, I choose to keep an open mind about any new theories/hypothesis'. Like always, I reiterate that human beings do not have all the answers to the questions they seek, therefore leaving room for discovery and marginally for recovery, say for possible miscalculations (perhaps the Archaeopteryx being placed as the first bird!). In any case, science is ever-changing (Dr. H) and in turn, a realm of infinite possibilities.
Even though I found these two articles to be a bit confusing, I realized that the new discovery would change how scientists interpreted the evolution of birds. Prior to the discovery of Xiaotingia, scientists believed birds descended from Archeopteryx. However, when Xiaotingia was plugged into the equation, the results differed. Archaeopteryx and Xiaotingia share enough features to be clustered together, removing Archaeopteryx from its original position on the diagram and placing it with Xiaotingia. The second article explained why Archaeopteryx and Xiaotingia are now classified together. They both would be grouped with deinonychosaurs, rather than birds. This exemplifies how science is not set in stone. As scientists continue to make new discoveries, our understanding of evolution changes.
First of all, I’m sorry about the late responses. I’ve been on vacation for the past two weeks or so. I haven’t had immediate access to a computer, and it hasn’t exactly been the first thing on my mind either. Hehe, sorry.
I briefly saw in one of Deepa’s posts that she read an article about science changing everything the author learned in school. When I first looked at the articles Dr. H posted, I had no idea what an Archaeopteryx was or why Xiaotingia zhengi was so important, so the articles really didn’t shake my core. Still, it is important to note that science is imperfect as with everything in the world. I remember back in freshman year when we were learning about evolution, I always wondered how scientists could distinguish whether a group of animals were descended from a certain species or they just happened to evolve similar features, which I remember learning the name of but not the actual word. (I remember CHON being the answer to everything!) How did they decide that this species converged with that one here and those species diverged there? I never bothered to ask in class, but these articles shed some light that even scientists don’t always know how to distinguish them either. What is mind blowing is that with all that science has discovered, there are still many things we have yet to uncover, something I think is very humbling in our fast-paced society.
What I find myself still wondering about is how a computer program can make those decisions about creating evolutionary trees. How do they enter those parameters into a computer?
Scientist: This new species we found in China has feathers, is pigeon-sized, and eats meat. I call it Xiaotingia zhengi!
Computing…
Loading…
And the computer spits out a tree with names of all the species in that group of animals. Somehow I doubt that’s what happens.
Those articles had way too many "sciency" words for me to understand them fully, but I got the general idea. For years, many scientists thought that Archaeopteryx was the original species that all birds today are descended from. However, the discovery of Xiaotingia zhengi throws a monkey wrench into into that theory. Although Archaeopteryx is still an ancestor of birds, it is now believed to have a smaller role than thought before. In my opinion, this new discovery just shows despite all the knowledge we have of the time before humans existed, we still know very little. This discovery has nearly revolutionized our knowledge of the origin of birds, and when this happens, it shows just how little me know about the subject.
Paleontology and evolution never fail to intrigue me in that they rely more on speculation than other branches of science, and as a result, any new data or findings can alter existing hypotheses to a great degree. These fields are a testament to the fact that science is incredibly dynamic and never stagnant. It is wonderful to see that experts in bird/dinosaur evolution have recognized this ever-changing facet of science and received the finding of Xiaotingia zhengi, hypothesized to be a distant relative of early birds, with an open mind. They have been willing to accept that perhaps the Archaeopteryx is not as closely related to early birds as previously believed and may be more closely related dromeosaurs and deinonychosaurs. This illustrates another important principle in science: when data and observations contradict existing hypotheses, scientists must be adaptive and willing to create new hypotheses. With open minds at the forefront of various scientific branches, science continues to grow both in terms of breadth and in terms of depth and details, as we observe in this case.
From a scientific perspective, it is absolutely amazing how phylogenetic trees are created. In these articles, we read how the discovery of the Xiaotingia zhengi revealed to us information about Archaeopteryx with the use of systematics and computer programs. I looked up more information on phylogenetics software and found a whole list of them on Wikipedia: http://en.wikipedia.org/wiki/List_of_phylogenetics_software. I was pleasantly surprised to find that at the heart of phylogenetics is one of my favorite subjects: statistics! Mathematics seems to be the basis of even the most theoretical fields--absolutely incredible! In addition to the mathematical aspect, I also found interesting how several cousin species and distant relatives can exist at the same time, but only one or a few were selected naturally to continue on the path of evolving into birds. There is a lot of uncertainty as to which species fill in the gaps, and new discoveries always have the potential to change theory. It's a fact that is simultaneously awe-inspiring and scary, considering that there may always be a species whose fossils are undiscovered that can greatly change the phylogenetic tree.
As for the cartoon, I love it! It took me a while to understand, naturally, considering I am very, very slow with jokes! :D
Paleontology and evolution never fail to intrigue me in that they rely more on speculation than other branches of science, and as a result, any new data or findings can alter existing hypotheses to a great degree. These fields are a testament to the fact that science is incredibly dynamic and never stagnant. It is wonderful to see that experts in bird/dinosaur evolution have recognized this ever-changing facet of science and received the finding of Xiaotingia zhengi, hypothesized to be a distant relative of early birds, with an open mind. They have been willing to accept that perhaps the Archaeopteryx is not as closely related to early birds as previously believed and may be more closely related dromeosaurs and deinonychosaurs. This illustrates another important principle in science: when data and observations contradict existing hypotheses, scientists must be adaptive and willing to create new hypotheses. With open minds at the forefront of various scientific branches, science continues to grow both in terms of breadth and in terms of depth and details, as we observe in this case.
From a scientific perspective, it is absolutely amazing how phylogenetic trees are created. In these articles, we read how the discovery of the Xiaotingia zhengi revealed to us information about Archaeopteryx with the use of systematics and computer programs. I looked up more information on phylogenetics software and found a whole list of them on Wikipedia: http://en.wikipedia.org/wiki/List_of_phylogenetics_software. I was pleasantly surprised to find that at the heart of phylogenetics is one of my favorite subjects: statistics! Mathematics seems to be the basis of even the most theoretical fields--absolutely incredible! In addition to the mathematical aspect, I also found interesting how several cousin species and distant relatives can exist at the same time, but only one or a few were selected naturally to continue on the path of evolving into birds. There is a lot of uncertainty as to which species fill in the gaps, and new discoveries always have the potential to change theory. It's a fact that is simultaneously awe-inspiring and scary, considering that there may always be a species whose fossils are undiscovered that can greatly change the phylogenetic tree.
As for the cartoon, I love it! It took me a while to understand, naturally, considering I am very, very slow with jokes! :D
After reading both of these articles, i have learned that one small discovery could lead to a huge shift in the research of evolution. By finding this small fossil, so many questions arose about the species already discovered. The discovery of the Xiaotingia zhengi led scientists to question the Archaepteryx. These articles showed me that the evolutionary model can always change as new discoveries are made. They also show that we still have a lot to learn about evolution and some of the facts we already know could change depending on new discoveries.
Personally this topic in general doesn't interest me. It's cool and all that the scientists have found a new species that can change the lineage of modern day birds, but it's kind of a waste of time. Maybe I'm just being ignorant but these species of been extinct for hundreds of years. Does it really matter if the Archaepoteryx speices was considered one of the closer relatives to modern day birds, but now with the discovery of the Xiaotingia species all that changes? Knowing this information doesn't change anything in the present. Maybe I'm just skeptical because even the scientists themselves are admitting their models for the bird trees are weak.
The discovery of fossils from the new species Xiaotingia has really caused a big stir in the ancestry of birds. It is intriguing how new archaeological discoveries such as the Xiaotingia have caused researchers' theories on the linage of many species. It is obvious that it is hard to make exact conclusions on the origins of many species since their is always a chance of a new discoveries which leads to changes. In this case the Archaeopteryx was considered the oldest ancestor to modern birds. But in the discovery of the Xiaotingia it has changed refuted that theory. I believe that it will be most probable that it will change again.
To be honest, reading both articles made my head spin. I can't really fathom the difficulty of figuring out the past of any type of animal considering the fact that no one was there and it takes a long time for any type of animal to evolve. Similar to the author of the article on the "Xiaotingia Zhengi" I don't think that the fuss made about the new discovery was worth it. Maybe it had replaced the Archaeopteryx as the first bird, maybe it hadn't. Science is constantly changing because of the discoveries that are made by scientists who, may or may not be searching for another answer. Being able to determine such factors and details from a fossil is a feat in and of itself. Finding another fossil just brings us closer to finding out more about the past of birds and dinosaurs.
The first article was rather vague, and perhaps that was why i was confused about the subject. The second article was much more forthcoming about the subject. It states that the xiaotingia is not the only discovery to have questioned the position of archaeopteryx. In describing the Archaeopteryx, it cleared up more of my confusion concerning the whole subject. The xiaotingia's discovery could very well, if there were more evidence put the archaeopteryx out of its position as the evolutionary turning point between dinosaurs and birds. It holds many characteristics that combine the best of both. However, at this point in time, the possibility of this happening is not as major as many have highlighted, there are many factors have to be considered before completely changing the evolutionary chain, which many scientists are probably reluctant to do. The Archaeopteryx which scientists refer back to when studying the transition from dinosaurs to birds is iconic and cannot be so lightly shifted to the side, unless there is substantial evidence.
Again, I give props to the scientists who study fossils. Fossils and rocks and evolutionary chains are not my forte. Going backwards in time and figuring out which type evolved into what which involved into the animals that we have today makes my head spin.
I found this article very interesting how scientists are able to find creatures through fossils. I found the fact about Xiaotingia living in China during the late Jurassic period, being about the size of a pigeon really interest me. Apart from that the fossil record is full offailed experiments and evolutionary dead-ends whichs make you not want not really know what creatures are out there and what still doesn't exist
This recent discovery has changed our view of historical evolution, for only about the thousandth time. Scientists frequently find new data that contradicts previous ones and a new theory is created while the old one is chucked out. This is seen all over every branch of science. While we can agree on the most basic of principles today, who knows what can happen if some genius finds some theory that contradicts something we take for granted?
My second point is even though the Archaeopteryx was moved into the dinosaur lineage and out of the bird family, both could have evolved together although they are both completely structurally different. An example of this idea in the present can be seen when you compare a shark to a dolphin. Both live in the water and look very similar on the outside since they have both adapted to the same surroundings. However, on the inside, both are completely different; one is a mammal while the other is cold blooded. If scientists do agree and conclude that this Archaeopteryx is indeed not a part of the bird family, then that does mean that it evolved and had to adapt to the same surroundings that the birds had to. Only more research and digging through Earth's crust for fossils and other treasures can help explain the past.
With my knowledge of dinosaurs based off a hazy viewing of Jurassic Park in the fourth grade, I read the articles without much understanding of paleontology. PZ Myers' description of building phylogenetic trees was especially fascinating; I was impressed at how modern technology has played such a huge role in helping scientists in the surely arduous task of piecing together the past. The discovery of Xiaotingia zhengi in particular reveals the difficulty of deciphering evolution. As both articles explained how this fossil has shifted evolution groups, the authors make a point in reminding us that new research and development constantly modify previously accepted notions in the ever-changing realm of science.
Dinosaurs was one of the topics that I used to read about when I was around the age of five. In a picture book about dinos, the author had drawn that dinosaurs evolved from birds. Later on, I found out that the first "bird" was Archaeopteryx and was very much interested. Back then, I had no idea that this was a theory until recently. To me, this article shows, once again, that science is always changing due to new discoveries, or just walking into a museum with a particular fossil. It interests me that new information, such as this, will be able to change the perspective in which we see a particular area. It forces me, and others, to question what we hold is true.
When Darwin was coming up with his theory of evolution, he probably had similar problems: a species he thought was a direct ancestor is in fact not. Human nature would cause us to be frustrated and to be on the verge of quitting. However through hard work, Darwin was able to prove his idea of evolution. Hopefully, one scientist will lead us to see which dinosaur is the first "bird".
On a whole separate note, the dinosaurs from Jurassic Park were created by using frog DNA, if I am not mistaken. If information from movies are true, which in most cases they are not, then maybe dinosaurs are really related to frogs, not birds. (Not a theory, just a comment.)
Having little background on the history of birds, I found it difficult to understand the terminologies in the articles. What I understood is that there's always uncertainties in evolution; that the family tree of birds could never really be set in stone since there's bound to be tons of more discoveries that could alter/change any family tree. In general, any discoveries made could change our knowledge on the Universe's many details.
In the first article, after uncovering the new dinosaur fossil, the relations of Xiaotingia altered its family tree because of its newfound data. This single discovery made paleontologists reassess who/what the early birds really were/was. The gist of the second article is similar to the first; a comparison of related birds and dinosaurs had created a new family tree.
Collectively, the articles support the idea that science will be forever-changing; this tells us that what we think we know now could potentially be changed by future discoveries.
There were some things I did not understand from the articles but I was fascinated about the fact that birds evolved from dinosaurs. From what I understood from the articles, Achaeopteryx was known as the first bird but now, that fact is challenged by the appearance of Xiaotingia. This discovery does not only affect Archaeopteryx but also makes slight changes to the evolutionary tree. I don't fully understand the details of the comparisons of these fossils but it is pretty interesting how just one discovery can completely change an old, well-known knowledge.
As of this weekend, I have a newfound obsession with Richard Dawkins – he’s incredible. And as I watched some of his lectures/interviews, I was constantly reminded of this blog post.
In one of his interviews, someone challenges evolution with the argument that there are so many gaps in the theories of evolutionists and those gaps are evidence of the existence of an intelligent designer (another post ☺). Dawkins responds by explaining that those gaps are simply areas where further research is encouraged and by no means discounts the great deal of evidence supporting evolution.
Xu’s findings are exactly what Dawkins refers to. It is research that may slightly alter what was previously thought, but only further strengthens Darwin’s ideas. I love how these blog posts are coming up in conversations that I’m having with friends!
On a side note, @Ahmed O, phylogeny is incredibly interesting. “A phylogenetic hypothesis is essential is you want to understand biological phenomena”, most of which have an evolutionary explanation. Darwin’s theory of evolution can tie together disparate biological facts into a single unifying framework. Theodosius Dobzhansky once said, “Nothing in biology makes sense, except in the light of evolution.” Studying evolution and continually researching it has a direct bearing on how society makes public policy and even, at times, on how we choose to run our lives.
For instance, modern diseases (such as obesity, diabetes, and autoimmune disorders) are present, in part, due to difference between our genes and an environment that is modified more rapidly than human genomes can evolve. Understanding this mismatch may help persuade a patient to change their diet as to obey the requirements of a genetic heritage that prevents us from accommodating excess surplus, refined carbohydrates and saturated fats from a steady intake of fettucini alfredo and the like.
So you see, evolutionary research – such as Xu’s – allows us to better understand the world around us, and in consequence, better understand ourselves. Although it seems irrelevant and dare I say…a waste of time, it builds on knowledge that will help us know how to live our lives. I strongly encourage you to read more about evolution and I guarantee that you will understand its importance and find a genuine appreciation of its majestic nature.
The fact that evolution is changing everyday and never concrete is mind-boggling in itself; however these articles were a new level of comprehension. Basically this article describes a paleontologist’s findings about the suspected first bird, Archaeopteryx. In the findings Xing Xu found out that the Archaeopteryx is closely related to a new identified species called the Xiaotingia. The findings are causing a controversy because the Xiaotingia is not closely classified with the birds, but rather a distant relative. In other words when new information was available about the Xiaotingia, it posed the questions of whether or not the Archaeopteryx is as closely related to birds as we previously thought. While I found this article confusing, it also amazed me how science always has room for change. For years we have thought that the origin of the bird was the Archaeopteryx, however with further research it has recently caused speculation on the issue. These articles are only a few examples of how the science world always has room for new discoveries.
I’m going to be honest and say that I found the first article to be somewhat confusing, but after reading the second article I actually learned a lot. Scientists now believe that the Archaeopteryx was not one of the earliest birds. Xiaotingia zhengi is now to be thought to have taken the Archaeopteryx’s place. I think that as more fossils are found and more research is conducted, that this dinosaur family tree will change again. I also think it is pretty interesting how Gerald Mayr thinks that the deinonychosaurs are actually birds themselves. These two articles showed that there is not a lot of support for many of the theories that have been formed. The more research that is conducted will help scientists fill in the missing gaps of the dinosaur family tree and help uncover the mysteries of where birds today evolved from. I think it will be very interesting to see how everything turns out.
The few things I got out of this article are that Archaeopteryx was a relative to the basal avians of modern birds. However with the discovery of Xiaotingia, it was obvious that Archaeopteryx had more relative features with this kind of species making its relation with modern birds more distant. Instead, Xiaotingia and Archaeopteryx was given its own classification on the evolutionary tree.
With Xiaotingia being discovered as one of the earliest birds this can explain why birds these days have their kind of diet. Xiaotingia was herbivore.
Other than that everything else was kind of a blur. The big picture here is that science is always changing and discoveries are being made everyday that can alter it. The discovery of Xiaotingia was an excellent example.
There have been proves of Archaeopteryx being the link between the historic dinosar and the modern birds. Like we all know it science is always changing and with the discories of the new fossil from china we have discovered that archaeopteryx is not the link between dionasars and our modern birds. This information was proven inaccurate and other discories were made like the Xiaotingia. The archaeopteryx is not the direct ancestor of our modern birds but was related to the basal avians so its more like a cousin. The fact that we keep finding more fossils means that there are still species we have not discovered and more evidence to connect the middle age dianosars to moderm birds.
The second article goes in more dept about the Xiaotingia. Xing lida and Liu yi reconstructed the Xiaotingia and show us the evolutionary changes that occured which helps us better understand the connecting between those species and our modern birds. The aritcle talks more about the history of these birds and because of many failures and weak reconstuction they are unable to predict what species gave birth to our modern birds.
I'm sorry to say this but dinosaurs are so boring to me. What I personally found to be interesting is that the fossils of this dinosaur has only been spotted in China. Shouldn't they also be found around modern day middle east as well? I remember learning a while back on how there were certain dinosaur fossils that were only spotted in South America and Africa, reason being that during the Jurassic period these two continents were once connected. Maybe more fossils of the Xiaotingia zhengi can be expected to be found in the near future.
While growing up I was always interested in dinosaurs and in fact becoming a paleontologist was actually the first career I wanted. But after reading these two articles I realized why I gave up on that career. Theories such as the first bird, possible extinction of dinosaurs, and other dinosaur related arguments are always changing. One moment scientists come up with one standout theory and a couple years later it becomes replaced. In my opinion, no matter how closely we study the bones and structure of dinosaurs and guess which of these two were really the first birds the fact that millions of years have passed has always preventing me from truly believing in these evolutionary theories. I find it hard to believe that there was actually a “first” bird. I think these two dinosaurs were just two dinosaurs on their way into becoming modern-day birds and were in a similar stage of evolution.
These two articles sum up one of the reasons that I love science: just one small discovery can lead way to a big change in belief. I mean, all it takes is one fossil to alter an entire scientific theory! The fact that the discovery of Xiaotingia has moved Archaeopteryx out of the direct line of the modern bird is a prime example of this phenomenon. What has thought to have been the scientific norm for years in regards to the origin of the modern bird has been completely shifted ... all by a pigeon-sized discovery! Out of the two articles, the fact that I found most interesting was in Yong's article when he stated, "Xiaotingia’s presence is crucial. When Xu re-ran his analysis with exactly the same species except for his new discovery, Archaeopteryx was restored to its original position as a proto-bird. This new specimen has made a big difference." This just goes to show that small details can alter the big picture. @Camille S., I also am fascinated at the role that technology plays in modern science. Without computers to piece together scientific data, who knows where we would be! Even so, it is clear that there are many holes to be filled in the evolutionary tree for modern birds. I'm sure that as more discoveries are made, we will eventually be able to pin-point where our modern birds truly came from. For now, kudos to Xu on his influential findings!
On a side note, the cartoon was hysterical! I think that what I'm most excited for about A.P. Bio is revisiting the topics that we learned about Freshman year, and gaining even more understanding about the world of Biology.
I found these articles very interesting and informative because this discovery changed the bird family tree and showed the Archaeopteryx is closely related to the newly discovered Xiotingia and showed that it is not a direct ansector of modern birds. this is interesting to me because one discovery made scientists and paleontologists indecisive on where to put Xiaotingia and Achaeopteryx, which was once considered one of the earliest birds, but with the new discovery, it shows that its more like a distant cousin.
Paleontologists have a very difficult job, that is constructing the evolutionary tree of all species. Every new fossil discovery could mean a revision to the tree. What makes this even harder is it is impossible to find all the fossils of species that existed on earth. There may be earlier species that existed and their remains are buried deep into the earth that cannot be reached. Every new discovery, such as Xiaotingia, brings us a step closer to finding the origins of species.
After reading these two articles for the first time, it's safe to say I was sufficiently confused. It took me a few re-readings, and even though I still don't really understand much about the specifics of phylogenetics, I was able to draw some general conclusions from the articles. From what I understand, paleontologists rely heavily on comparison when piecing together fossils to form an evolutionary tree. Because of this, one small discovery (such as the one discussed in these articles) can completely undermine the entire structure of a pre-existing evolutionary tree. Paleontologists have made incredible progress, but there will undoubtedly be other controversial discoveries that could potentially disprove what is currently accepted as the truth. This fragility is often misconstrued by opponents of evolution as a loophole in the theory, which is entirely false. If anything, it affirms that advancements in evolutionary research are continuously being made, and that scientists are headed in the right direction.
4) After reading these two articles I found that it was somewhat confusing but also quite informative. I never realized the extent to which one discovery could change an entire revolutionary history. Archaeopteryx was originally the base of modern bird evolution but now, with the discovery of Xiaotingia, its spot on the tree is in jeopardy. Although a lot still has to be proven, it’s very interesting to realize that this single discovery can alter our look on the bird species. These articles show that science is never finished. No matter how hard scientists work to prove something, one simple fossil can come along and switch everything up.
Though I agree that paleontologists have a difficult job, I don't see the significance of this article. The only way I can see this article affecting us in the present day is if scientists built a model using new data that this fossil could provide. Maybe the model could be used to set up other models which can be applied to other organisms in the present day. One thing that still amazes me about this is the thought that is required to be able do draw these many details, predictions and hypothesis just from studying a few samples of rock that are millions of years old.
These two articles were a bit confusing to me, but I seem to have the general picture. I also grasped a better understanding of the job of paleontologists. I used to think their only job was to dig up bones and fossils to contribute to scientific research but it seems to be more than that. After reading these articles i'm amazed as to how one discovery can totally alter the family tree. This is why evolution can be so complex because scientists are constantly discovering new things that can alter evolution groups. Not only did Xiaotingia take Archaeopteryx from its positions as the first bird, but also it created much debate in science. I found it interesting how the second article stated "Just as Xiaotingia moved Archaeopteryx out of the birds, the next find could move it back in-" This shows how science is constantly discovering new things.
Not going to lie, I found this quite difficult to understand as well, but I'll try to answer the best I can. I'll start by saying this is very good proof that science is, indeed, ever-changing! There are always new things you can learn in science; most like math. You can never discover enough! Even though they found that the Archaeopteryx is not the oldest bird, they will still take account that the Archaeopteryx is a piece of the evolutionarily puzzle, maybe just not as important anymore. Although I think just because a scientist disproves another scientists' theory, does not make him the victor. Someone can come along and prove him wrong as well! Nothing is really set in stone when it comes to evolution, things are constantly getting disproved. I don't really have a passion for this topic, so I really don't have a lot of argumentative input.
Amongst all the z's and x's and deinonychosauriengiopteryxidae's, I was able to gleam this: For the longest time, Archaeopteryx was considered the earliest grandaddy-Big-Bird common ancestor of all modern-day birds. It's so famous, there's even a Pokemon character based on it o.O (google archeops) In keeping with traditional scientific whirlwind revelations that change everything we know and love, Archaeopteryx has been displaced by the newly discovered Xiaotingia zhengi. It is now thought to be a branch cousin to the earliest birds, and perhaps not truly a bird in the first place. It's interesting knowing that these scientists accept both that this new evolutionary tree makes more sense with the new data as well as that anything we know is subject to change at any moment with a new discovery. These articles are great examples of the dynamic nature of scientific knowledge. Sorry, Archaeopteryx :/
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