Question

Любой лишний груз мешал бы при полете. Какие изменения произошли в скелете для облегчения полета птиц? Какие изменения произошли во внутреннем строении?

Answer 1

У них легкие кости, есть киль без которого они б не смогли летать.
ну и у них в легких есть воздушные мешки. И оперение.

Answer 2

Changes in the Skeletal Structure for Flight

Birds have undergone several changes in their skeletal structure to facilitate flight. These adaptations include modifications in the bones, sternum, and the presence of specialized flight muscles.

1. Hollow Bones: One of the key adaptations in birds is the development of hollow bones. These bones are lightweight and contain air spaces, reducing the overall weight of the bird's skeleton. The air-filled cavities also provide buoyancy, making it easier for birds to stay airborne.

2. Fusion of Bones: Another adaptation is the fusion of certain bones to increase strength and stability. For example, the fusion of the neck vertebrae into a single structure called the synsacrum provides support for the body during flight.

3. Modified Sternum: The sternum, or breastbone, in birds is highly modified to accommodate flight muscles. It is enlarged and has a prominent keel, or carina, which serves as an attachment site for the flight muscles. The keel provides a larger surface area for the attachment of powerful flight muscles, enabling birds to generate the necessary lift for flight.

4. Reduced Number of Bones: Birds have fewer bones compared to other vertebrates. For example, they have fewer tail vertebrae, which reduces weight and increases maneuverability during flight.

Changes in Internal Structure for Flight

In addition to skeletal adaptations, birds have also undergone changes in their internal structure to facilitate flight. These adaptations include modifications in the respiratory system, circulatory system, and reproductive system.

1. Respiratory System: Birds have a unique respiratory system that allows for efficient gas exchange during flight. They have a system of air sacs connected to their lungs, which allows for a continuous flow of oxygen-rich air. This enables birds to extract more oxygen from each breath and sustain the high metabolic demands of flight.

2. Circulatory System: Birds have a highly efficient circulatory system that supports the increased oxygen demands during flight. Their hearts are relatively large compared to their body size, and they have a higher red blood cell count, allowing for efficient oxygen transport to the muscles.

3. Reproductive System: Birds have also made adaptations in their reproductive system to accommodate flight. They have evolved to lay hard-shelled eggs, which are lightweight and provide protection for the developing embryo. Additionally, birds have a unique reproductive behavior called cloacal kissing, where the male and female press their cloacas together to transfer sperm during mating.

These adaptations in the skeletal structure and internal systems of birds have allowed them to become highly specialized for flight, enabling them to navigate and survive in their aerial habitats.