-
Asked by asks520meet on 16 Oct 2024.
-
Zoe Vance answered on 16 Oct 2024:
There probably isn’t one big reason why birds evolved, the individual features that we’d consider to make something a bird like wings, feathers etc. likely existed long before birds did. Also birds had actually evolved from a sub-group of dinosaurs before the big extinction so they existed at the same time as some dinosaurs – it isn’t like a sudden overnight change from dinosaurs to birds.
I’m no dino (or birb) expert, but the answer to why anything evolves in a particular direction is basically always that the new form is in some way better suited to the current environment than the old one, so you need to ask what birds might have that would have given them an advantage. Palaeontologists seem to think that getting smaller was a pretty important step, as was developing beaks, and there are sensible reasons for why these things might have happened. Smaller size might have helped with flight, or more generally it can be a better strategy when times are tough because smaller bodies are more efficient, and beaks are a very useful tool to have when you don’t have hands! It’s possible these features also allowed birds to take up some new diet that other creatures existing at the time couldn’t access; evolving into an unoccupied ‘niche’ is a very common pattern in evolution.
-
-
Kirsty Lindsay answered on 16 Oct 2024:
Sometimes with evolution the answer is just “because they could”. There was some advantage to being more bird-like than the being more non-avian dinosaur like because avian dinosaurs ( AKA birds) survived to the modern day, So avian dinosaurs got more bird-like until they where just called birds, but they are also still dinosaurs.
Kinda funny to think that turkey dinosaurs are are made with actual dinosaurs! 🙂
-
Tina-Jaine Haigh answered on 27 Nov 2024: last edited 27 Nov 2024 14:19
Animals (and humans) are born with small difference to each other, or small differences to what is typical for that species, all the time. These differences can be random, but some are useful, and some less useful. Evolution happens when an animal is born with a small difference to the others, which just by chance happens to give them some advantage over the others. That individual is more likely to survive and have babies. If their babies have the same characteristic, they are also more likely to survive and grow up to have babies. The characteristic can start to get exaggerated if animals with the same characteristic have babies together.
Being able to fly probably started with being able to jump unusually high or far, and that’s useful because it might get you out of the way of a predator trying to eat you. Having a flap of skin under your arms would help you jump higher or further because it helps to push down on the air. Having feathers on your arms which are all aligned to form a big flat area would have the same effect. So if some dinosaurs were born with just slightly more loose skin under their arms than the other dinosaurs, they would have a small advantage. Or if some were born with their feathers just slightly sticking out behind their arms, they also would have a similar advantage. If they have babies together, they are starting to get the beginnings of wings.
Flying squirrels are a good sign of how this change might have gone. Flying squirrels don’t really fly. They just jump really far. They are gently falling as they move through the air. The big area of skin under their arms helps to ensure their fall is very gentle. It gives them a small amount of control over their movement through the air by adjusting their arms, but nowhere near as much control as a bird. I’ll bet in 1000 years there are mammals similar to squirrels who properly fly.
Comments