HB BB Flashcards
Birds are one of the largest groups of vertebrate animals on land with around how many known species?
10,000
What % of bird species are adapted for flight?
99%
What anatomy and physiology of birds can by used to define them? (8)
1) Bone structure
2) Wings
3) Feathers
4) Eyes
5) Feet
6) Egg laying
7) Eating and drinking
8) Digestion
Who is considered one of the best fossilised links as the transitional species between the non-avian dinosaurs and the modern-day birds showing feathers and wings?
Archaeopteryx
What are the largest and smallest species that currently exists?
9ft tall ostrich
two-inch-long bee hummingbird
Most bird skeletons actually weigh less than the weight of all of their feathers. True or False?
True
A bird’s voice box is not the larynx and vocal cords as is the case with mammals, but a bony structure that is unique to birds called
the syrinx
What are some of the adaptations that has allowed birds to evolve for flight capability? (11)
- LUNGS have special air sacs and combined with hollow bones. It allows gasses to flow around the body more easily, meaning each breath intakes goes further and does more work than a mammal. Oxygen is exchanged on both in and out breath.
- LARGE HEARTS, in ratio to body size, bigger and stronger than a mammal. Smaller birds have a faster heart rate than larger ones. A small bird in flight can have a heartbeat over 1,000 beats per minute.
- Compared to most other species, their bodies are more compact.
- Most of their large muscles and organs are located near centre of gravity (slightly below and behind wings).
- High blood pressure.
- High metabolism.
- Vertebrae are fused for a stable air frame.
- Leg muscles close to the body and tucked in during flight.
- Their wings/forelimbs are attached closer to the centre of gravity and are father from the head than in any other animal.
- Coracoid, furcula and the scapula form a tripod in the skeleton which supports the wings.
- They also have feathers… The wing primaries and secondaries are aerodynamic giving lift as is the whole shape of the wing. With enough wind some species just need to open their wings to take off.
Birds that have passive soaring wings are? (3)
- Eagle
- Stork
- Buteo
Birds that have active soaring wings are? (3)
- Albatross
- Gannet
- Gull
Birds that have elliptical wings are? (5)
- Sparrow
- Blackbirds
- Thrush
- Crow
- Grouse
Birds that have high-speed wings are? (5)
- Swift
- Falcon
- Turn
- Sandpiper
- Duck
Feathers serve many functions (5)
- Flight
- Temperature regulation
- Communication
- Waterproofing
- displays and courtships
Even the smallest bird, such as a Robin, could have anywhere between how many feathers?
1000-3000
Feathers fall into one of 7 broad categories…
- Wing
- Tail
- Contour
- Semiplume
- Down
- Filoplume
- Bristle
The feathers specialized for flight. Uniformed, windproof surface, these feathers are asymmetric, with a shorter, less flexible edge, which prevents the feather twisting in flight.
Wing feathers
These are similar to wing, but are arranged more in a fan shape and are used to support precision steering while in flight. Typically, there are six pairs of feathers. To some birds, these feathers have evolved into showy ornaments and are useless in assisting with flight but might come in handy for attracting a mate.
Tail feathers
These are small feathers covering the bird’s body which gives the overall shape and colours, arranged in an overlapping pattern like tiles on a roof. The fluffier bases are hidden against the body and the outer-waterproof section are exposed. In some birds these are brightly coloured, in others, uniformly drab, or in camouflage colours.
Contour
Often hidden below other feathers on the body with maybe only the tops exposed. They have a soft hook-like structure, rather than smooth appearance, creating a fluffy insulating layer
Semiplume
similar to semiplume, except held right against the body, they are short, soft and branched widely to trap body heat. Due to being so close they have no resemblance of colour or pattern, just small and fluffy looking
Down
A very short feather, which function a lot like whiskers on a mammal. They help with sensing the position of the contour feathers
Fioplume
These are mostly found on the head, they protect the birds’ eyes and face, a bit like extended eyelashes on a mammal. Especially found around the beak areas and are often overlooked
Bristle feathers
Feather colours are formed in two ways…
- Pigments in the feather themselves.
- the way light is refracted on the structure of feathers
Pigmentation colour in birds comes from one of three groups…
- Carotenoids
- Melanins
- Porphyrines
Feather colours produced by plants, and come from either eating plant material, or eating another animal that has eaten a plant. Responsible for the bright yellows, brilliant oranges and reds seen in birds, as well as mixed shades like olive-greens.
Caroteniods
Occurs as tiny granules in colour or skin and feathers. They are darker colours, black, browns, pale yellows and reddish browns. The function is not just about colour, feathers are stronger and more resistant to wear, this can be noted how a lot of bird species have black feathers on their wing tips – even white birds, since these feathers are subject to a lot of wear
Melanins
When a bird or an animal is referred to as melanistic, it means
their body has produced more melanin than normal, giving them an almost black appearance
?? are produced by modifying amino acids. They fluoresce a bright red when exposed to UV light. They produce a range of feather colours such as pinks, browns reds and greens
Porphyrines
When do birds moult?
later summer into autumn
The eyes can account for what % of the bird’s head weight
15%
Unequal toes – what most birds have from waders, to birds of prey, one toe is always longer
Anisodactylie
Toes arranged symmetrically in pairs – seen a lot in woodpeckers, parrots, or birds that climb a lot.
Zygodactylie
Three toes
Tridactylie (Emus)
Two toes
Didactylie (Ostriches)
Swifts have all four toes that point forwards…
pamprodactyl
Similar with Aniso – with three toes forward, one toe back, except toes 2 and 3 are often fused for much of their length and sometimes they are missing toe 3 entirely - Kingfishers
syndactyle
The bird stomach is comprised of two organs
proventriculus and gizzard