Learning Target: Birds meet their needs on land, in water, and in the air.
Birds are found in the Kingdom Animalia
Birds are found in the Phylum Chordata
Birds are found in the class Aves
The study of birds is called ornithology
A scientist who studies birds is an ornithologist
Birds are found in the Phylum Chordata
Birds are found in the class Aves
The study of birds is called ornithology
A scientist who studies birds is an ornithologist
Characteristics of Birds:
- Feathers
- Hollow, lightweight bones
- Endothermic (warm-blooded)
- Scaly feet (birds are related to reptiles)
- Specialized respiratory system for flight
Feathers
A feather is one of the soft, fringed plumes that cover the bodies of birds. Some feathers are tiny and downy, while others are large and brilliantly colored.
Feathers are covered in oil to keep them water proof - "like water of a duck's back" - this oil is secreted from a preen gland. Preening is a behavior that replaces the oil on feathers, and repairs broken links on the vanes.
There are 3 types of feathers:
- Down Feathers (provide insulation)
- Contour Feathers (cover head and body, provide coloration)
- Flight Feathers (on wings and tail, provide lift)
Why are down feathers used in clothing and bedding?
Where do they come from?
Where do they come from?
Bird Bones
Birds have a lightweight skeleton made of mostly thin and hollow bones. The keel-shaped sternum (breastbone) is where the powerful flight muscles attach to the body. Birds have a smaller total number of bones than mammals or reptiles. This is because many of their bones have fused together making the skeleton more rigid. Birds also have more neck (cervical) vertebrae than many other animals; most have 13 to 25 of these very flexible neck vertebrae (this helps them groom their feathers). Birds are the only vertebrate animals to have a fused collarbone called the furcula or wishbone and a keeled breastbone. Below is a diagram of a typical bird skeleton.
Endo-Thermic (Warm Blooded)
Warm-blooded creatures, like mammals and birds, try to keep the inside of their bodies at a constant temperature. They do this by generating their own heat when they are in a cooler environment, and by cooling themselves when they are in a hotter environment. To generate heat, warm-blooded animals convert the food that they eat into energy. They have to eat a lot of food, compared with cold-blooded animals, to maintain a constant body temperature. Only a small amount of the food that a warm-blooded animal eats is converted into body mass. The rest is used to fuel a constant body temperature.
Cold-blooded animals often like to bask in the sun to warm up and increase their metabolism. While basking, reptiles will lie perpendicular to the direction of the sun to maximize the amount of sunlight falling on their skin. They will also expand their rib cage to increase their surface area and will darken their skin to absorb more heat. When a reptile is too hot, it will lie parallel to the sun's rays, go into a shady area, open its mouth wide, lighten its skin color or burrow into cool soil. Some cold-blooded animals, such as bees or dragonflies, shiver to stay warm when in a cold environment. Fish who live in areas where the winters are cold move to deeper waters during the colder months or migrate to warmer waters. Some fish have a special protein in their blood which acts like anti-freeze to help them survive very cold water temperatures. Snakes, lizards, toads, frogs, salamanders and most turtles will hibernate during cool winters. Some insects die when it gets too cold, however others survive by migrating to warmer areas or moving underground. Honeybees stay warm by crowding together and moving their wings to generate heat.
There are many advantages to being warm-blooded. Warm-blooded animals can remain active in cold environments in which cold-blooded animals can hardly move. Warm-blooded animals can live in almost any surface environment on Earth, like in arctic regions or on high mountains where most cold-blooded animals would have difficulty surviving. Warm-blooded animals can remain active, seek food, and defend themselves in a wide range of outdoor temperatures. Cold-blooded animals can only do this when they are warm enough. A cold-blooded animal's level of activity depends upon the temperature of its surroundings. A reptile, for example, will increase its body temperature before hunting and is better able to escape predators when it is warm. Cold-blooded animals also need to be warm and active to find a mate and reproduce.
There used to be a saying about somebody who doesn’t eat much — “she eats like a bird.” But how much does a bird typically eat? As a rule of thumb, the smaller the bird, the more food it needs relative to its weight.
Specialized Respiratory System
A four chambered heart prevents oxygen rich blood from mixing with oxygen poor blood - it is a double-loop.
Lungs are connected to air-sacs, which fill with air during inhalation. The air then is released from the air sacs when the bird exhales - this means that the bird receives oxygen during inhalation and exhalation.
The lungs are connected to the trachea.
Lungs are connected to air-sacs, which fill with air during inhalation. The air then is released from the air sacs when the bird exhales - this means that the bird receives oxygen during inhalation and exhalation.
The lungs are connected to the trachea.
Bird Digestion
Birds digest food quickly, they can't afford the extra weight. The have no teeth, the breakdown of food occurs in the gizzard - sometimes birds swallow rocks to assist in digestion. The crop stores food. Mother birds regurgitate food stored in the crop to their babies. Waste exits through the cloaca and so do eggs.
Bird Brain
Think again the next time you call someone “bird-brained.” You might be giving them a compliment.
Bird brains are small. An emu’s brain accounts for 0.06% of its body mass, whereas a human’s is 2%. Yet some birds are capable of
Bird brains are small. An emu’s brain accounts for 0.06% of its body mass, whereas a human’s is 2%. Yet some birds are capable of
- using tools
- recognizing themselves in the mirror
- saving food for future use.
- Solve complex puzzles
- Learn to talk (they just mimic sounds they hear)
Scientist have determined that bird brains have a high number of neurons compared to other animals. The higher density of neurons allows for more connections, increasing the capacity for information processing in a small container. Songbird and parrot brains accommodate two to four times more neurons than rodent brains of similar weight, and around twice as many as some primate brains.
Beaks and Feet