By the early twenty-first century Archaeopteryx is most widely considered to be a bird, but one with many dinosaur-like characteristics. Quite surprisingly, Archaeopteryx has been considered to have been similar to a modern bird called the Hoatzin (Opisthocomus hoazin) which is native to upper South America. Although not a perfect match, juvenile Hoatzin possess claws that enable them to climb branches until their wings are strong and developed enough to enable flight.
Being popularly defined as a bird. the obvious question would be could Archaeopteryx fly? It would seem that the answer depends on whether you mean powered flight or just gliding, but first we need to consider what is necessary to enable flight in the first place. First and foremost would be the feathers since birds don’t rely upon extended flaps of skin or membranes like other flying/gliding vertebrates. Birds require special kinds of feathers which as you might guess are called ‘flight feathers’, and these are found on the rear edges of the wings for primary lift, and the tail for steering. Aside from lift these feathers can also be angled by wing and tail movements to alter things like drag to control flying speed in a similar fashion to the flaps on the wing of an aeroplane (in fact engineers copied this from watching birds).
A flight feather is generally much longer than it is wide and is reinforced by a rigid spine that runs down the length of the feather so that it keeps straight and does not bend with the up and down movements of the wing. These kinds of feathers are like those on the wings of Archaeopteryx, which means that the genus has at least one of the things necessary for flight. The flight feathers on Archaeopteryx though are not exactly like the feathers of modern birds because they lack things called barbicles. Barbicles are like tiny hooks on the fronds of the feather that hook around the fronds of the feather they are next to, the barbicles of that feather then hook onto the next and so on. Barbicles are simple features but they allow all of the feathers on the wing to act as one large complete unit rather than lots of smaller individual ones. This reinforces the wing, making the feathers not only stronger but capable of providing more lift. The fact that Archaeopteryx lacked these barbicles does not mean that they could not fly, just that Archaeopteryx were not yet evolved into modern forms, something we already knew. As time went on and barbicles began to appear, they became more standardised, but the principal here is that they had to evolve somewhere, and it seems that it was not with Archaeopteryx, but possibly a later and more advanced form.
The next thing to consider is was Archaeopteryx capable of producing a ‘flight stroke’? A flight stroke is a movement of the wings that allows for the production of lift to get the body into the air, and then repeating that stroke or a variation of to stay in the air. The key to producing a flight stroke is to have flexibility, ideally to be able to move the wings (which remember are really just modified arms) above the back for an extended down stroke which can produce a greater amount of lift. The analysis of Archaeopteryx skeletons however is not promising. In modern birds the shoulder is aligned dorsally (to the spine) whereas in Archaeopteryx the shoulder has a sideways alignment. This is a throwback to more dinosaurian ancestors, but it terms of flight it means that the wings of Archaeopteryx did not have the same range of motion as modern birds. This means that at best if Archaeopteryx could fly, it could not fly as well as modern birds.
A reduced range of motion does not mean that Archaeopteryx could not take to the air. By holding the arms out to the sides it is conceivable that Archaeopteryx could be gliders since the developed flight feathers of the wings would have still acted to reduce the rate of descent. The wings of Archaeopteryx were fairly short and rounded on the ends, similar to birds that live in woodland environments today. Assuming Archaeopteryx lived in these environments, and it seems quite possible, then they may have climbed trees with the claws on their wings for either food or shelter, and then jumped and glided to the next tree along. But so far we have only looked at two areas that are necessary for flight, and from here we need to go from beyond just wings and feathers.
Powered flight by flapping wings requires the development of muscles capable of maintaining the same repetitive movement for a long time, and these muscles in turn require skeletal attachments to secure them in place. The muscles for flight in modern birds are concentrated on the breast (analogous to your pectoral muscles) which is why birds tend to have really deep and round chests. These large muscles require an equally large attachment, and in this case it’s the sternum, the solid bone that connects the ribs together. If you have ever carved a chicken or a turkey, then you will know that as you cut into the breast you have to cut around a large flat bone that rises up from the ribs; this is the sternum.
Evidence for strongly developed flight muscles is mixed between specimens of Archaeopteryx, but one thing for certain is that there is no enlarged bony sternum like that seen in modern birds. Some specimens currently assigned to Archaeopteryx though show the possible presence of a cartilaginous sternum which would have functioned in the same way as a bony one. Cartilage is a tissue that can be rigid in life, but rarely survives long enough to fossilise except in cases where the cartilage has become ossified (turned to bone) before death. Also going back to carving chickens, while the main sternum is bone, there is always a cartilaginous extension to this bone. If Archaeopteryx possessed and enlarged cartilaginous sternum, then they may have been able to maintain a modified flight stroke that although not as efficient as a modern bird, may have been able to allow for sustained powered flapping flight. Otherwise all Archaeopteryx would be able to do was manage a few flaps of the wings before becoming tied and having to stop, though this in itself might have been enough to allow an individual to get airborne so that it could then glide the rest of the way. It is also conceivable that from such a point as this, later decedents that modified skeletons and musculatures could eventually extend the length of time that they could keep flapping until they evolved into birds more similar in form to what we know today.
An additional bit of support for flight in Archaeopteryx actually comes from analysis of the brain, specifically its size. Two studies by Witmer and Alonso et al., and both in 2004 showed that relative to the size of the body, the brain of Archaeopteryx was actually quite large. Reconstructions of the brain also indicated that the area dedicated to vision accounted for one third of the total brain size, while the areas of muscle co-ordination and hearing are also well developed. The inner ear of Archaeopteryx is also more like that of modern birds that non-avian dinosaurs. What this all means is that the brain of Archaeopteryx was already hardwired with all of the necessary features for controlling wings and moving in a three dimensional environment like you would if you were flying.
When you piece together the brain, the skeletal structure, the musculature and feathers of Archaeopteryx, you are left with a creature that could definitely glide, and was perhaps capable of limited powered flapping flight. In this respect Archaeopteryx might not have been a graceful flyer, but it possessed everything necessary for further developments that appeared in later descendants. It should always be remembered though that Archaeopteryx is a transitional form, if it were better developed for flight it probably would not be so valuable for our understanding in bird evolution.
Alert Buff and Strike.
Delayed Cunning Rampage.
Alert on Escape Evasion.
Resistant to rending (33%), swap prevention (75%) and taunt (100%).
The first of the new 2.9 update creatures and it’s the famous Archaeopteryx. Looking at her stats, they seem good enough for a creature with the flock mechanic. Reasonable health, damage and speed. She has the usual unique ability sets that we have come to expect from creatures with the flock mechanic. For a Rare she seems reasonable. Mine is still levelling so I have yet to field her and get a hands on impression.
What are your thoughts on Archaeopteryx?