2024-06-24

How are there so many species of birds?

Like any animal, a new species typically emerges from breeding isolation. The geography of certain habitats can create physical barriers that require different modes of adaptation to best thrive. The actual speciation often occurs when random acts of genetic mutations cause behavioral or physical changes to new offspring. When a mutation helps the birds' survival, then they are able to thrive better than their counterparts. Some mutations create characteristics that get the birds killed; thus, not passing those genes to any offspring. A mutation can also have no effect on a bird's survivability.

Concentrated populations of the same species can lead to a lot of interbreeding. When his happens, the population remains similar to each other, making it harder for speciation to occur. When a population is split by geographical barriers, different mutations are likely to accumulate among the different sects; thus making homogeny less likely to happen.

Eventually, sufficient differences in genetics make interbreeding between the two populations impossible. Subtle differences in feathers, singing, and other mannerisms are enough to put-off any attempts at interbreeding. This is reproductive isolation, just one of the many examples of isolating mechanisms.

2024-04-22

How did birds "modernize"?

Ancient avians that sported toothy beaks apparently vanished in the Cretaceous Extinction 65 million years ago. The toothless avians ended up being the ones who survived and prevailed during the harshest conditions. Fewer predators allowed these birds to thrive and diversify greatly. Birds became warm-blooded (endothermic) during this era; this means that their body-temperature remains consistent regardless of environmental conditions. Animals that are endothermic typically have a higher metabolism compared to cold-blooded (ectothermic) creatures such as reptiles and amphibians. Being warm-blooded meant that birds could perform high-aerobic movements such as wing-flapping without over-exerting themselves. A consequence of this is the constant requirement of foraging for food. While people can usually live for weeks without eating, some birds will die if they miss even a single day of food.

The functions of feathers also became multi-faceted, hence the different types of feathers (powder-down, contour, flight, cosmetic, seasonal plumage, etc.). Though, there is some speculations as to how the first birds used their feathers. One theory suggests that ancient birds would glide down from the tree-tops. Here, protofeathers were actually elongated scales--made to increase surface area and thus jump further. Natural selection would prioritize longer scales so gliding would become better and eventually don the insulation advantage with feathers. This would mean they needed to be good climbers which archaeopteryx probably was.

Another possibility is the "ground-up" theory. This postulates that flight came from running bipeds. Endothermy was needed for predators for fast/sporadic movements, and feathers would develop for insulation, eventually forming an airfoil to capture prey better and faster. This idea came from the idea that dinosaurs were fast-moving bipeds.

2024-04-15

Where did birds originate from?

The origin of birds is constantly debated among paleontologists because our understanding is so vague, but we do have some prevailing theories. The archaeopteryx, from "archae" meaning "ancient" and "pteryx" meaning "wing", was a dinosaur that had a lot of bird-like qualities. At about 30cm tall, it had feathers and a toothy beak. It had no keeled sternum, so its ability to fly was weak, but the ability to glide is certainly likely. Based on the fossil-record, we know that their feathers looked almost the same as they do in modern times and that they covered the creature, especially on their arms and tail.

These discoveries were essential in finding the intermediary between dinosaurs and birds. This is interesting because this means that reptiles are more closely related to birds than they are to amphibians. Since the discovery of the archaeopteryx, there have been some (but not many) fossil-discoveries that support the bird-dinosaur connection. This link has been theorized since the 1860s but was not widely accepted due to various skeletal features, such as the furcula (wishbone) being absent in ancient animals. By the 1970s, it was plainly obvious that birds had descended from theropods and is now a commonly accepted theory.

2024-01-18

Do crows remember what you look like?

A crow's ability to remember the faces of humans is not science-fiction. A crow will not remember most people who walk by, but they will recall who their enemies and allies are. Someone who harasses a flock in an egregious way will find them getting dive-bombed, pecked at, or defecated on. Some folks who treat a flock with kindness (especially with food) may be treated to some "gifts" that they find.

Adapting to an urban habitat has caused a lot of species to push their imitation ability to the limit. Pigeons, great tits, starlings, and other noteworthy perching birds have had to look toward rubbish to find easy sources of food. By observing people and other birds, these birds have been able to open containers of food that was believed that only people can open. For example, milk jugs that had the cardboard lids could be removed to pillage the contents inside. Imitation is impressive feat that a lot of potential mates will seek in a partner, such as song imitation as discussed earlier.

Birds have an understanding of what behaviors to not imitate. If a crow watches their friend get killed, the observers will know to avoid that. This includes seeing birds try new foods and rejecting them. Some birds have learned how to open automatic doors. Foods on display at a grocery store look appetizing to most perching birds and will try to trip the door-sensor to get it to open. These types of behaviors are not instinctual, but rather learned behaviors. Understanding bird intelligence as a whole is fascinating because it helps teach us what part of our mind is intuition and which is intellect.

2024-01-10

Is bird intelligence instinctual or learned?

Some birds, like corvids and parrots, rely more on their wits than other birds and even mammals. It is, in fact, an adaptive trait; one that has evolved selectively. This means that a bird's problem-solving ability is passed down from one generation to the next; where the smarter individuals are more likely to succeed and reproduce. Intelligence tests are hard to quantify between different species. There are lots of variables and different types of intelligences that make comparison difficult. For example, a blue-jay may be able to perform better than chimpanzees when it comes to finding lost objects, but a chimp regularly displays superior photographic memory.

Birds have shown an impressive ability to distinguish sounds and shapes. They have also proven well to be better at counting than numerous mammals. They also have a good sense of weight detection. We know this because we almost never see birds attempt to land on a branch, only for that branch to snap. Studies have shown that seed-eating birds can detect if the inside of a sunflower seed is empty or not--an amount that is light enough to equate a dozen milligrams. Crows and ravens may be the birds that are studied the most because of how well they excel in their tests. They have been shown to succeed in solving simple physics puzzles; for example the water displacement test. This is where the bird must drop objects into a vase-like container to get their food to float to the top where their beaks can reach. Some successful tool usage has also been documented. The caledonian crow may be the brightest of the bunch; parents will demonstrate tool-use to their offspring before they leave the nest.

2024-01-02

How do birds learn so fast?

The brains of a bird are hard-wired to learn quickly. Being the first to recognize patterns helps them acquire food-sources faster than their competitors. If there is an abundance of food, many will seek to hide or cache their food items, such as peanuts and acorns, in small cavities in trees or underground. The part of the brain that helps animals remember where things have been placed is called the hippocampus. Caching birds, like corvids and woodpeckers, have a larger-than-average hippocampus, allowing them to recall the locations of nuts cached over the period of several months. This is especially useful in winter when the snow melts.

Another complex behavior that birds display is flight. This is why the parts of avian brains that utilize motor-control are well developed compared to mammals'. Another useful characteristic is their ability to sing so well starting at such a young age. Singing behavior is ingrained from their youth as they learn their melodies from their parent(s). Some birds are capable of song even without parental presence, which suggests that their singing ability is intrinsically linked to their DNA, which is remarkable on its own. Singing is not the only reason that birds will vocalize. They can make vocalizations to alert others, to express pain, to defend territory, and imitate (sometimes for fun). The ability to learn songs is wired between two different song-control centers in their brain. Any injury to these areas (or even in between) can disable the bird's ability to sing.

2023-08-26

How smart can a bird get?

Some island-birds are especially vulnerable to human activity. Birds, such as the dodo and great auk, lived devoid of predators altogether. This resulted in a non-reactive behavior once they saw their fellow birds get killed off. They were not wired to react to predators. Other birds, like geese, are famous for their inability to identify whether an egg is theirs or if it an inanimate object. A lot of birds, however, are really good at rooting out parasitic eggs. Cowbirds will attempt to lay an egg in the nest of another bird, hoping that those parents will raise that baby for them (and eventually out-compete their fellow hatchlings). These parents have since then learned to cast out eggs that don't look exactly like the ones they lay, down to the finest speckle. This has created an interesting back-and-forth evolutionary tactics between the parasitic egg-layers and the rest.

Another talent that birds have learned is identifying songs. Not just from other avian species, but from individuals from their flock; this is a well-studied phenomenon that occurs among corvids. Corvids, such as jays, crows, ravens, and magpies, are understood to be one of the smartest family of birds in the world, rivaling only parrots. Both groups of birds have been shown to be able to differentiate the faces of humans. These birds will remember people who have harmed (or tried to harm) their flock by swooping at them and alerting their friends with their calls.

Most birds can not only distinguish songs and sounds, they can also recall shapes, and can count; more specifically one-tone sounds and a two-tone sound. They are also smart when it comes to weight and pattern recognition. We know this because they know how thick a branch needs to be to hold their weight. They can know when a sunflower seed has been husked or not judging by weight alone. Pigeons are renowned for their ability to identify people through images as well as tree-types. Pigeons as well as some corvids and parrots have passed the mirror test; meaning they can identify themselves in a reflection, giving them a remarkable sense of self-awareness.

Learning new ways to acquire food via imitation (not instinct) is a great indicator of avian intelligence. Being forced to adapt to urban environments has created new opportunities to acquire food. For example, great tits in Britain learned to twist lids off cardboard lids/bottles, blue jays will learn from other jays who spit out undesirable food and avoid those contents, and house sparrows have been seen to trigger electronic sensors on the doors of grocery stores by hovering in front of them. Understanding bird intelligence is one of the best parts of ornithology.

2023-08-18

How come a bird's other senses aren't as sharp?

Avians' sense of taste is perhaps their weakest sense. They have less than 1% of the taste buds compared to that of a human, and they're typically located in the back; probably to help them decide if an object is edible. Their tongue is used more as a tool to position food (rather than tasting) before going down the gullet. This is why some birds have tongues that are long or forked or rigid. A bird's sense of smell is generally not much better. Most are capable of telling apart different species of birds as well as finding sources of nearby food. New World vultures such as the turkey vulture, have an exceptional sense of smell. The scents of rotting meats stimulate their olfactory nerves more than any other scent, letting them scavenge more successfully.

Birds have an additional hidden sense that is truly remarkable. The Earth's magnetic field is not only helpful for people navigating, birds use it to help orient themselves too. Recent discoveries have established how they are capable of this feat. Doves, such as the homing pigeon, have a remarkable ability to find their home-nest no matter where in the world they are. Now we know that is likely because of a special protein in their eyes called "Cry4"; it is ultra-sensitive to blue light which helps them to see which way magnetic-north is. European robins were discovered to produce higher amounts of Cry4 during migration season. Research is ongoing to determine whether it's all birds that have this sense, or just some of them.

2023-08-10

How good is a bird's hearing?

Along with sight, birds have an excellent sense of hearing. Although they don't have ear lobes like most mammals do, they do have fine covert feathers that act as ear lobes. Owls have perhaps the greatest hearing of all living things. Their faces are shaped to help funnel sound directly into their inner ears. The way we hear is because tiny bones vibrate a small spiraling organ in our inner ear called the cochlea. The spiral is full of ultra-sensitive neurons that will send electrical signals to the brain only if that section of the cochlea vibrates. Most people can hear a range of sounds from 20Hz to 20,000Hz. So, a hum that is, say, 5,000Hz will only vibrate a narrow section of the middle of the cochlea. Birds have a similar structure compared to mammals; however, their audible range is narrower, but can vary greatly among species.  Nocturnal birds are the best at hearing. Part of what makes owl-hearing so sharp is their ability to sense sounds from the vertical dimension as well as the horizontal. Essentially, for people, we are great at finding the source of a sound at eye-level. This is because sound travels slow enough that we know which ear is receiving the noise first. However, some owls, such as the barn owl, can detect a sound-source from the vertical and horizontal planes, giving them excellent precision when hunting rodents.

When it comes to producing sound, birds are among the best in the animal kingdom. Instead of a larynx, like mammals do; birds produce sound from their throat called the syrinx. The syrinx has a more sophisticated structure and uses most of the exhaled air to produced sound, far more than a persons' who would use only about 2%. An avian's trachea forks into two tubes where the syrinx straddles. This allows for birds to produce two different sounds at once, granting songbirds the ability to sing in pretty and elaborate melodies. Though, not all birds use their syrinx to sing, birds such as the lyrebird and corvids (crows and jays), prefer to mimic. These vocalizations can help communicate with other birds of their species. Mockingbirds can mimic hundreds of noises; mate selection is often determined by how well their mimicry skills are.

2023-08-02

What makes bird-vision so excellent?

Out of all the stimuli that a bird can sense, its sight is some of the best among all living things. Generally, where their sight and hearing excel, it's their sense of smell that typically lacks. There are also some birds that have tactile sensors on their beak. Part of the reason why birds can see so well is because their eyes are locked in place; they can not be rotated like ours can. This explains why they are constantly moving their head. This is because their eyes are so big that there is no room in their skull for muscles to move them. In mammals, we have muscles that pull left and right; and up and down on the eyeball, letting us see and focus on objects without having to move our head, but we have relatively smaller eyeballs as a result. Just like in mammals, birds of prey have eyes on the front of their heads so they can focus on the prey they target. Meanwhile, birds that are often prey, like most perching birds, have eyes on the sides of the head that allow them a wider field of view, letting them watch for predators behind them. Bigger eyes mean sharper vision. A greater surface area on the interior means more room for more light-receptors, which is why the birds with the best vision are owls and eagles which have elongated eyes.

There are two types of light receptors: rods, which detect black & white imagery (which are great for nocturnal birds) and cones, which detect color (great for diurnal birds). The cone-counts in diurnal birds are 2-5x denser than ours. Meaning, they can see more colors than we can. Day-time birds are also built with anti-glare; very helpful for wading birds. Nocturnal birds have a very dense rod-count; this helps them see the night almost as if it were day. Birds can generally see in the ultra-violet spectrum. We can not comprehend what colors they can see in that light frequency, but we can use tools that help us see what things glow under a UV light. Being able to see those frequencies means that birds can easily see other birds as well as mammals' urine-spots just to name a couple examples. Some birds, such as homing pigeons, have built-in polarizers, which help them navigate in the sunlight. 

2023-07-25

How does excretion work?

After a food item, whether it be seeds, fruit, insects, fish, rodents, etc., has been digested and sapped of its nutrients, the body works to get rid of it. For mammals, water dilutes the excrements present in urine and scat. Since water is heavy, and most birds need to be mobile, they will instead excrete highly concentrated semi-solid droppings. It's called uric acid, and its toxicity is potent. Birds of prey, especially those that dine on mammals will spew pellets out of their mouths, which contain hair, fur, and/or bones. Other birds, such as gulls, shrikes, and cormorants are known to cast pellets as well.

Regurgitation is the act of vomiting recently consumed food and birds do this for a plethora of reasons. The most common reason it to help chicks eat partially digested food. While it is easy for a songbird to catch a worm or insect to feed their babies, it is not easy for fish-catching birds like herons and storks who instead will regurgitate their day's catch to help feed their young. Vultures and condors, which have the most acidic stomach-acids in the world, will gorge themselves; sometimes, to the point where they can no longer fly. If they feel threatened while in this state, they might vomit in order to fly away faster, acids and all. This is a great deterrent to mammals, especially those with sensitive noses. Some parrots, including lovebirds will regurgitate some of their food as a way to show kindness and appreciation to another lovebird. Sometimes, a bird will regurgitate a food simply because it did not sit well in their crop. 

2023-07-18

How do birds keep themselves warm?

Feathers coat a bird's body like fur coat. This helps insulate their heat, preventing heat from escaping their bodies. Birds can also fluff up their feathers, giving them a more rotund appearance and causing less heat to leave their bodies. Cold birds will often tuck in their head and neck closer to their torso, sometimes under their wing to better insulate themselves. If it's cold enough, birds will shiver, which helps their metabolism to emit more heat. Some species, like inca doves and penguins will huddle themselves closely. Other species, such as grouse, have been observed burying themselves in the snow. Sheltering in tree cavities, dense foliage, and brush piles are not uncommon either.

Birds, in desperation, will willingly reduce blood-flow to their legs by one of two ways: 1.) constricting their arteries that go to their legs, or 2.) autonomously transfer the heat from their arteries directly to the veins before the blood goes to the leg. By occasionally letting warm blood to enter the leg, the leg does not freeze. This is why it is common to see birds in cold environments to stand on one leg, while the other is tucked up into their belly-feathers. Another skill that some birds can do called torpor. It is like a deep sleep, and their body temperatures drop as they enter this hibernation-like state, though it does not last nearly as long. The most popular method of temperature-control, however, is migration. By moving north or south, birds will have a greater chance at surviving by moving to a more ideal climate. But that is a story for another time.

2023-07-10

How do birds keep themselves cool?

Compared to all animals of similar size, birds have the largest hearts relative to their bodies. Hearts expand and contract which pumps the blood quickly throughout their bodies. Avian bodies are specialized for optimal blood-flow. A consequence of this is constant high-blood-pressure which can cause heart failure in high-stress environments. Birds also metabolize quickly, that means that they are able to digest quickly. Perching birds, which consist of over half of all bird species, have the highest metabolic rates. As a result, they need to eat more food relative to their body to survive. Faster movement means burning energy quicker. Other activities, such as gliding and brooding, don't burn energy nearly as fast, thus, are sustainable for long periods of time.

As birds exert energy, their bodies heat up. They can not sweat like mammals can, but can perspire through their skin. They can pant or some large birds can do what is called gular fluttering, which is when they expand and contract their neck muscles as a means to cool off.  Birds can also sit in the shade, bathe, or soar high to cool themselves.

2023-07-01

What makes bird respiration special?

Since flying is a physically demanding activity, birds burn off an exceptional amount of energy when doing so. To accomplish this, they need highly efficient organ systems that are able to supply that. People's body temperatures are 37°C. This is called homeostasis. Bird-homeostasis is significantly hotter at 40-44°C. With the raised temperature, nerve impulses travel faster and muscle strength increases. The consequence of this is higher energy requirements. This is why bird's need more food compared to animals of similar weights.

The respiration system for birds is more complex than that of a mammal's; avian lungs are much more efficient, in fact. Air is sucked into large air sacs, not a diaphragm; these can take up to 20% of space in their body. For us, our lungs work like bellows. Oxygen needs to touch the lung-interior in order to complete the exchange and much of the air don't exit the lungs. A lot of oxygen gets wasted because of this. The bi-directional air-flow is not as efficient compared to a bird's uni-directional air-flow. Once a bird takes in their first breath, the air sacs near the rear are filled, the next exhalation pushes that air through the lungs which is textured more like a sponge. Here, capillaries, which are like ultra-narrow blood vessels, have a semi-permeable membrane, meaning oxygen molecules can pass through the walls and re-oxygenate the blood-cells. The de-oxygenated air enters another set of air sacs before getting exhaled, completing the cycle. This type of breathing allows birds to breathe where the air is thin, miles above sea-level.

2023-06-23

What is special about avian muscles?

Flying requires an immense amount of muscular strength; most of which comes from, not there arms, but rather their pectorals (breast) muscles. Bird pecs typically account for almost a quarter of their total body mass. For most birds, lift is achieved from the down-stroke of a wing-beat, meanwhile, hummingbirds and penguins use both the up-stroke and the down-stroke to hover/swim. During long flights, wing-beats can be autonomous, like breathing. Albatrosses have been observed to be able to sleep as they soar; this is because of the aid received from the updrafts of ocean waves. Having these muscles attach to the keeled sternum is remarkable because in most vertebrates, the arm muscles attach to the spine or back-bones.

Muscles in general work by contractions; the body would not be able to move with them nor the skeleton. Without skeletons, birds would be blobs. We know this because muscles are attached to the bones which are anchored by firm muscular fibers called tendons. Expanding and contracting the muscles causes the bones to push and pull the bones they are attached to. The energy exerted on these muscles to produce flight is part of the reason why birds need to eat so much food in a day. Some birds, such as hummingbirds, beat their wings dozens of times in one second. If birds didn't have a high metabolism, then they wouldn't be able to acquire the nutrients needed for surviving.

2023-06-13

How do avian skeletons differ from other animals?

The skeleton of a bird is similar to that of a bipedal mammal. They have four limbs that connect to a spine which connects to their skull with joints in most of the same spots. In order to fly, however, the bones are required to be smaller and more hollow to reduce weight. Because of this, impact injuries are often fatal. From an evolutionary standpoint, sturdiness is sacrificed for mobility. Grounded birds, such as ostriches, tend to have stronger bones since the flight-advantage is no longer present.

The furcula, or wishbone, is the fusion of what would be their two clavicle bones; its flexibility helps with respiration. Flight muscles are attached to the keel, a protrusion from the sternum. In fossilized birds, the shape of the sternum is how we know which ones were capable of flight. Bird ribs are braced for reinforcement and have more flex to them, so they don't break as easily. The short tails of a bird extend from the spine enough to form proper tail-feathers. Their pelvis, which acts as a girdle, joins the spine and legs. There are fewer carpal (wrist) bones in birds than humans, yet maintain more flexibility in their 'wrist' movements. Bird femurs are very short compared to most mammals. The next two bones are much longer, the tibiotarsus which is like their fused calf-bones, and then the tarsometatarsus, which is like fused bones of a human's upper-foot--hence the reason for the appearance of the 'backwards knee'. This makes all birds digitigrades, like cats and dogs. Their spines have significantly more vertabrae than people do; it's why most of them are able to turn their head 180° which is essential for properly preening their own wings and backs. 

2023-06-05

How do birds eat without teeth?

Birds expend a lot of energy to fly, so a high-calorie diet is necessary to keep up with their energy expenditure. Birds have a high metabolism which means that they digest food quickly. Being able to utilize nutrients quickly is essential to their high mobility. Like mammals, birds can be carnivores, omnivores, or herbivores. Since they don't chew their food, everything they eat is swallowed whole through the esophagus. Most birds have a special organ in their throat called the crop. Sometimes referred to as the craw, the crop is used for food storage prior to digestion. The gullet and crop are able to expand considerably, sometimes becoming visible from the outside. Cormorants and herons are some examples of birds that can gorge on massive amounts of food and still function like nothing happened.

Most birds have two stomachs. The first one proceeds the crop and is called the proventriculus which looks like an expanded part of the esophagus. Here, acids break down the food into nutrients. Afterwards, the stomach contents enter the second stomach, the gizzard. Being the larger of the two, this stomach grounds up and pulverizes the food. Gizzards are lined with rough grit materials that function like molar teeth; this is especially useful for seeds which require the most grinding. Gizzards can intensify seasonally, most notably in the winter where insects are harder to find and the diet has to be changed to seeds, nuts, and other plant matter. In some birds, such as herons, the gizzard and the proventriculus are the same organ.

2023-05-27

Which beak is the best one?

Beaks are one of the defining characteristics of birds; they're crucial to their survival. The shape of a beak alone is enough to tell what kind of food they eat, the kind of fliers they are, their behaviors, and sometimes which sex they are. Raptors have hooked beaks that are great for tearing flesh; toucans have massive beaks for crushing food; herons have dagger-like beaks for spear-fishing; pelicans use theirs for netting; woodpeckers for chiseling wood; hummingbirds for nectar-feeding; crossbills, corvids, etc. for nut-cracking. Whether the beak is used to cut, crush, catch, probe, peck, stab, seize, filter, transport, or tear, we can always learn from their wielders how their beak is used best.

Beaks have a bony interior and a keratin exterior; some have more flex than others, meaning they can bend without breaking. Dowitchers use their flexible beak to open the tip of their beak to snatch prey in deep mud. American woodcocks and curlews have sensitive beaks which help them find food on the ground. Parrots and corvids have been known to use their beak for tool-use--a skill that scientists once thought only primates possessed. Although bird tongues are not as sensitive as mammals', they are still an essential component to eating. Birds use theirs to identify edible food items, position the food, crush, swallow, and more. Some tongues have barbs on them to prevent prey from escaping as well as filtering out water. Most woodpeckers have a very long tongue that is also barbed, some of which excrete sticky saliva, which is useful for capturing insects.

2023-05-17

How do bird feet work?

It is a misconception to presume that birds have a backwards knee. That bend is actually their "ankle". Their actual knees are usually obscured by the feathers on their flanks, very close to their body. Talons are like the claws on a bear. In addition to perching, walking, and hopping, bird feet are useful for climbing, preening, holding food, swimming, and attacking. Most birds are anisodactyl, meaning they have three front-facing toes, and one rear-facing toe called the hallux toe. Some birds, like parrots and woodpeckers, have two rear-facing toes and are great for climbing. A lot of shorebirds such as pelicans, cormorants, ducks, and geese have feet that are palmated, or webbed. The extra skin helps them paddle their feet as they float; they're also useful for walking on loose surfaces. Coots (as well as some other waterfowl) have two or three fleshy lobes that appear along their toes; they spread out as they kick in the water and fold back when walking on surfaces or flying. Ospreys have pronounced scales on their soles to achieve a tighter grip on the fish they catch. Some birds, including blue herons, have semi-palmated feet (webbing is only present between their outer and middle toes). They also have a serrated talon on their middle toe which helps with preening.

2023-05-10

How big can wings get?

The size and shape of a wing depend on their utility. While long, narrow wings are better for gliding, short broad wings are quick upward flights such as a chicken or a turkey; so why can't these birds sustain a long, lateral flight? This depends on their wing-load. A Wing-load is the weight per square area of wings; high wing-loads mean a heavy body (ex. chicken). Grouse and hawks are similar sizes but hawks don't bear a heavy wing-load. Larger wings aren't always better; having bigger wings means more weight, thus less mobility. Then there's the aspect ratio, which is the length of the wing per the width; a higher difference means more gliding and less flapping. Going back to the albatross; their heavy wing-loads are offset by their higher aspect ratio, making them the ideal glider, but terrible for vertical take-off. Low ratios mean more flapping.

To determine the largest wing in the world would depend on how they're measured. The wandering albatross and great white pelican have the longest wingspans measuring at 3.7m and 3.6m respectively. Though, the Andean condor (3.3m wingspan) may bear the greatest wing-load and still be able to soar; they can weigh up to 15kg.

2023-05-01

How are birds so aerodynamic?

The ability to fly has proven to be very advantageous for survival, especially when it comes to fleeing, migrating, and attacking. Birds are able to fly because the lift they produce with their wings is greater than the force that is pulling their weight down. Wings are specially shaped to be as efficient as possible; the less energy exerted when flying, the fewer calories they need to consume to compensate. Airplane airfoils are modeled after the shape of bird wings. The shape of the wings force the air above to move out of the way faster, creating a brief decrease in air pressure, just like that of an airplane. Unlike airplanes, however, most birds are capable of vertical take-off. The way the two overcome drag is different as well. Because of their rapid movements of the wings and light weight, birds do not experience turbulence. A lot of birds also have alula feathers which is a patch of small feathers between their coverts and primaries (where their thumb bone would be essentially) that helps generate additional lift.

 There are different forms of flight too. Flight can be sustained by wind alone. Albatrosses can go days without flapping their long wings. Birds of prey like to begin their flights by falling and using the momentum to catch lift. Wing-flapping creates thrust and lift; it is energy intensive and is most efficient at medium-speeds, like the mileage of a car (for reference, ~40mph is when your vehicle is the consuming the least gasoline.) Hummingbirds are capable of hovering. This is most energy intensive form of flight and is accomplished when they motion their wings in a figure-8 pattern. Kestrels and kingfishers can hover too, though not as well and not nearly as long.

2023-04-25

When do new feathers grow in?

Feathers can get worn out over time, so birds will often molt to grow new ones. Molting is when birds shed their feathers to make way for new growth. Most adult birds molt once a year, typically before winter. The reason for that is because regrowing a new coat of feathers takes energy, and Autumn is the time where there not much egg-laying, brooding, migrating, freezing, etc. going on resulting in basic plumage. The yearly molting patterns have been used to identify birds that otherwise look the same. Molting can help contour feathers (or the outermost feathers) to renew its density, an essential for birds like penguins. Molting usually does not occur all at once; a complete molt takes a lot of times. A second molt can occur before breeding-time, they acquire an alternate plumage, often more colorful than before. For most birds, the brighter and more saturated the color(s), the more healthy and fit they are for finding mates. Some birds, such as ptarmigans, have a special alternate-plumage for summer that turns their feathers brown; it helps them to camouflage in the Alaskan tundra. Some birds molt relatively quickly, sometimes it happens twice a year when it's convenient. Males can have different molting patterns from females.

2023-04-19

What types of feathers are there?

Feathers perform a plethora of functions. Some are used for flying, others for insulation, and some for beauty. The feathers on the wings and tail are used for flight. The longest wing-feathers are the primaries and attach to their carpal (hand/wrist) bones; next to those are the secondaries which attach to the radius/ulna (forearm) bones. The pigment that darkens the feathers, melanin, is helpful for maintaining durability, especially at the wing-tips. Most birds have about 10 primaries, give or take a few; the number of secondary feathers vary greatly.

Contour feathers are the smaller feathers on the bird's body that provide insulation and water-proofing. The ones that form at the base of the wing are called covert feathers. Tail feathers help with flight, their speed, tree-climbing, balancing, and beautifying. Beneath contour feathers are often semi-plumes and down feathers; these are the fluffy feathers that don't interlock. Their tiny and fluffy nature help further insulate the bird by trapping air and keeping warm. Some birds have feathers that act more like bristles, which can function as whiskers and eye-lashes. Not all is known about these bristle-feathers since their purposes are not always apparent.

2023-04-10

What's in a feather?
 

Feathers primarily serve three functions: Flying, insulation, and beauty. Birds have anywhere between 1,000-25,000 feathers depending on the species and their environment. Waterfowl and arctic birds will have more feathers than most due to their insulating properties. Feathers account for 15-20% of a bird's body-mass; compare that to their skeleton which is typically less than half that.

Like nails/scales, feathers are made of keratin. The parts of a feather include the calamus and rachis (which make-up the shaft), the vane, the tiny stringy parts are the barbs, and the microscopic extensions of the barbs are the barbules and barbicels which hook together the other barbs to form a lattice, giving the feathers a soft, fabric-like, texture. It is important that these feathers are well cared for; otherwise, they will become dirty, unaligned, and riddled with insects, inhibiting a bird's ability to fly, to insulate, or to feel pretty.

2023-04-03

What are the implications of a flying lifestyle?

Bird anatomy optimizes bipedal balance; some are more adapted to water and prefer floating to walking or perching. Their minds and bodies are adapted to flock behavior too. For example, birds that generally live a solitary lifestyle, such as the Great Blue Heron, will still find themselves grouping themselves in seasonal colonies called a heronry. These are formed during the mating season in the spring-time. So although, not all birds fly in flocks, they will usually give their own species preferential treatment.

The lack of forelimbs has given birds unique traits for spined animals. For example, an increased number of neck vertebrae. This allows them to be more flexible and utilize their beak better. Whether they use their beak for preening, cleaning, eating, digging, pecking, communicating, courting, fighting, etc., beaks have are a crucial tool to a bird's survival. The more we study birds, the more we learn about the practicality of the beak.

2023-03-26

How do we know a bird is a bird?

In the realm of classification, knowing which animals are which is essential to the study thereof. Knowing an animal's taxonomy helps us determine which animals' traits/behaviors/aspects are shared and which are unique to the specimen. While mammals like platypuses and whales blur the conventional understanding of mammals, modern bird identification is comparatively straight forward. If it has feathers, then it is a bird. All birds also lay eggs and are warm-blooded. This puts them in the class: Aves--just under the phylum: chordata (spined). Flight is not an essential feature of a bird because then that would rule out important bird-families, such as penguins, kiwis, and ostriches.

Having wings instead of hands, paws, or claws make for unique evolutionary features. Having their weight minimized makes flight possible. Unlike reptiles, fish, and mammals, all birds lay eggs; this is to keep them mobile and light-weight. Having a high metabolism (fast digestion), no teeth, and hollow bones means less mass; thus, less mass to overcome gravity.

2023-03-19

What goes into conservation?

The conservation status of all bird species range from Extinct to Least Concerned with various levels of endangerment in between. Where a bird might fall on this spectrum entails different types of protection from legislation. It's important that these categorizations are constantly updated and reflect accurately or else a species that becomes vulnerable will miss out on much-needed protections and go extinct. Online resources such as https://www.allaboutbirds.org/ and https://ebird.org/ maintain updated records on birds and their statuses as well as additional information and resources to making this world a better world for birds.

Inaction from 100+ years ago has led to the extinction of at least a hundred bird-species directly related to human activity. Parrots, herons, sparrows, and raptors that will never be able to see the light of day. Animals that we will never get to learn from; they teach us so much about our Earth and about ourselves. There are likely hundreds of other birds that have gone extinct in the last few hundred years because they were never documented.

The largest woodpecker ever seen, the ivory-billed woodpecker, was declared extinct in 2021. The woodpecker garnered so much infamy that it was nick-named the "Lord God Bird". Among ten other birds were also declared extinct that year; this is primarily due to the lack of legitimate sightings in decades. This is just in America.

Inaction today can easily cause dozens more to disappear from our lives. In the last fifty years alone, NA has lost over 25% of their entire bird population--the primary causes being from habitat loss and climate change. The effects from both will continue to escalate if people remain complacent. There is hope, however. NGOs (Non-government Organizations), government bureaus, international co-operatives, local community groups, and other humanitarian institutions have been established with the purpose of the conservation of our feathered friends. By outlining the species that warrant additional protection, unintended side-effects have become minimized. Pollution controls are, in general, becoming stricter, and more people and politicians are understanding the reality of climate change. 

2023-03-15

What counts as birding?

There is never a shortage of labor that needs to be done.

Being able to identify birds from afar is a must. It is a skill that no one has perfected because some species look identical to another. However, there is always some quirk, some behavior that is unique which helps differentiate the different species.

Counting birds is also a crucial activity that needs to be done. While counting whole populations is typically nigh-impossible, estimates can be made by counting the number of birds of a species in a particular area. This helps determine not only the density of the species' presence, but also the range.

How far west can you be and still encounter wild blue jays? How far south do ravens go? How far will barn swallows migrate?

These are questions that regular residents can find out we all just wrote down when and where we see certain birds.

The timing is important because when a bird a seen can tell us when seeing the bird would be rare/common. Sometimes, birders will encounter "accidentals" or individuals that have wandered off their expected path. Spotting an accidental could mean the introduction of a new group to a new habitat. It's an event that can cause a disruption to a fragile eco-system. The sooner we can identify an introduction like this, the more time we'll have to prepare to predict the long-term consequences of such events.

Bird-counts can also tell us how fast a population is changing. If a species is rapidly declining unexpectedly, then immediate action (usually from the government) is needed to prevent a population from facing extinction.

2023-03-09

Bird-watching, bird researching, or simply "birding" is an activity that could be done anywhere in the world. From city high-rises to the frozen tundra, birds are apparent in every biome in the world. Birding has low barriers for entry, so starting up does not require a big investment.

But why would people want to study birds?

Bird observations lead to curious discoveries. We know now how albatrosses are able to soar for miles without flapping their wings, or why some owls prefer burrowing in the ground instead of trees, or how penguins are able to survive the unforgivable weather. Although advance-level research are sometimes paywalled behind scientific journals, new information about birds are published online daily. Wildlife conservation is an ongoing struggle among governments and societies. As human civilization advances and the populations increase, the more habitats become threatened as a result. Thus, the scientific discourse on the matter is more relevant today than ever before.

Each week, I am going to share my new findings regarding ornithology, the study of birds, in order to help better understand the avian world around us--that maybe one day, I will be able to give back to that avian world after all the things that birds have done for me.