Friday, November 30, 2012

Biology Experiments for Teachers. Binocular Vision, Eye Dominance and Location of Stimuli

Binocular Vision: Experiment

(a) Keep both eyes open and hold a pen or pencil upright at arm's length.

(b) Quickly move the pencil to come exactly in line with a more distant vertical object, such as a window frame or lamp-post.

Biology Experiments for Teachers. Binocular Vision, Eye Dominance and Location of Stimuli

(c) Close and open the left eye.

(d) Close and open the right eye.

(e) Note any change in the apparent position of the pencil and whether it was the closure of the left or right eye which produced it.

(f) Which eye did you use in lining up the two objects?

Discussion

Although both eyes are kept open to line up the pencil and the distant object, only one eye, the dominant eye, is used to determine the alignment. When this eye is closed, the pencil will appear to 'jump' sideways. It is closure of the dominant eye which produces the jump because, according to the eye now remaining open, the pencil and distant object are not in line. If the student is slow to line up the two objects he or she may be aware of a double image of the near object. Nevertheless, the student is still likely to select the image from the dominant eye.

Awarness of Location of Stimuli. Experiment

(a) Place a glass marble on a non-slippery surface, e.g. on the page of an open notebook.

(b) Cross the first and second fingers of one hand and press on the marble with the tips of these fingers.

(c) Close your eyes and roll the marble firmly, forwards and backwards, side to side and then with a circular motion for about 30 seconds.

(d) Notice any unusual impressions you receive from the fingers.

Discussion

1 The subjective impression should be as if there were two marbles with the fingers pressing
between the two.

2 The areas of the finger-tips employed, with the fingers not crossed, would normally be stimulated only by two surfaces separated in space.. The connections that exist between the receptors and the brain are, presumably, the foundation for this interpretation. When the two areas are stimulated simultaneously by the same object in the absence of visual evidence, the brain makes its usual interpretation, giving the sensation of two objects.

The results also show that we normally rely on information from several sources for our
interpretations. If the subject watches the fingers and marble, it is far more difficult to elicit the impression of two objects.

Biology Experiments for Teachers. Binocular Vision, Eye Dominance and Location of Stimuli
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D G Mackean is the author of GCSE Biology, IGCSE Biology, and many other Biology text books. He has a site of Biology Teaching Resources at http://www.biology-resources.com which includes a bank of experiments for teachers, sample PowerPoint presentations, and many biological drawings

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Monday, November 26, 2012

113 Facts About Animal Cruelty

Animals caught in traps can suffer for days before succumbing to exposure, shock, or attacks by predators. Traps often kill "non-target" animals, including dogs and endangered species. To cut costs, fur farmers pack animals into small cages, preventing them from taking more than a few steps back and forth. Crowding and confinement is especially distressing to minks- solitary animals who occupy up to 2,500 acres of wetland in the wild. The frustration of life in a cage leads minks to self-mutilate- biting their skin, tails, feet- or frantically pace and circle endlessly. "PETA investigators witnessed rampant cruelty to animals. Workers beat pigs with metal rods and jabbed pins into pigs' eyes and faces." Snakes and lizards are skinned alive because of the belief that live flaying makes leather more supple. Piglets are separated from their mothers when they are as young as 10 days old. Once her piglets are gone, the sow is impregnated again, and the cycle continues for three or four years before she is slaughtered. Approximately 3 to 4 million cats and dogs- many of them healthy, young, and adoptable- must be euthanized in animal shelters every year. Cows produce milk for the same reason that humans do- to nourish their young - but on dairy farms calves are taken away at 1 day old. 1 day old calves are fed milk replacements (including cattle blood) so that their mothers' milk can be sold to humans. Animals can suffer brain damage or death from heatstroke in just 15 minutes. Beating the heat is extra tough for dogs. Each year, approximately 10,000 bulls die in bullfights. Most cows are intensively confined, unable to fulfill their most basic desires, such as nursing their calves, even for a single day. Cows are fed unnatural, high-protein diets-which include dead chickens, pigs, and other animals. Overall, factory-farmed animals, including those on dairy farms, produce 1.65 billion tons of manure each year. Kid goats are boiled alive to make gloves. The skins of unborn calves and lambs - some aborted, others from slaughtered pregnant cows - are considered "luxurious." About 285 million hens are raised for eggs in the US. In tiny spaces so small they cannot move a wing. The wire mesh of the cages rubs off hens feathers, chafes their skin, and causes their feet to become crippled. Before 1986, only four states had felony animal cruelty laws. Glue traps cause terror and agony to any animals who touch them, leaving them to suffer for days. In one study, 70% of animal abusers also had records for other crimes. Sealers often hook baby seals in the eye, cheek, or mouth to avoid damaging their fur, then drag them across the ice to skin them. Arsenic-laced additives are mixed into the feed of about 70 percent of the chickens raised for food. Every year, nearly a million seals worldwide are subjected to painful and often lingering deaths, largely for the sake of fashion. Scientists estimate that 100 species go extinct every day! That's about one species every 15 minutes. Every year in the US, 50 million male piglets are castrated (usually without being given any painkillers). More than 15 million warm-blooded animals are used in research every year. The methods used in fur factory farms are designed to maximize profits, almost always at the expense of the animals. To test cosmetics, cleaners, and other products, hundreds of thousands of animals are poisoned, blinded, and killed every year. In extremely crowded conditions, piglets are prone to stress-related behavior such as cannibalism and tail-biting. Farmers often chop off piglets' tails and use pliers to break off the ends of their teeth- without giving them any painkillers. For identification purposes, farmers cut out chunks of young pigs ears. Animals on fur farms spend their entire lives confined to cramped, filthy wire cages. For fur, small animals may be crammed into boxes and poisoned with hot, unfiltered engine exhaust from a truck. Engine exhaust is not always lethal, and some animals wake up while they are being skinned. Larger animals have clamps attached to or rods forced into their mouth or anus so they can be painfully electrocuted. Bird poisons attack birds' nervous systems, causing them to suffer seizures, erratic flight, and tremors for hours before dying. If you drink milk, you're subsidizing the veal industry. Male calves are often taken away from their mothers at 1 day old, chained in tiny stalls for 3-18 weeks, and raised for veal. After they are taken from their mothers, piglets are confined to pens until they are separated to be raised for breeding or meat. Although chickens can live for more than a decade, hens raised for their eggs are exhausted and killed by age 2. More than 100 million "spent" hens are killed in slaughterhouses every year. Forty-five states currently have felony provisions for animal cruelty. (Those without are AK, ID, MS, ND and SD.) Dogs used for fighting are chained, taunted, and starved to trigger extreme survival instincts and encourage aggressiveness. Dogs that lose fights (or refuse) are often abandoned, tortured, set on fire, electrocuted, shot, drowned, or beaten to death. Cows on average product 16 lbs of milk per day. With hormones, antibiotics, and genetic manipulation? 54 lbs a day. Humane treatment is not a priority for those who poach and hunt animals to obtain their skin. Alligators on farms may be beaten with hammers and axes, sometimes remaining conscious and in pain for 2 hours after skinning. Investigation of animal abuse is often the first point of social services intervention for a family in trouble. A Canadian Police study found that 70 percent of people arrested for animal cruelty had past records of other violent crimes. Dog fighting and cock-fighting are illegal in all 50 states. Hoarding of animals exists in virtually every community. Well-intentioned people overwhelmed by animal overpopulation crisis. The consequences for hoarders, their human dependents, animals, and the community are extremely serious- and often fatal for animals. Declawing is a painful mutilation that involves 10 amputations - not just the nails - but the ends of toes (bone and all). The long-term effects of declawing include skin and bladder problems and the gradual weakening of cats' legs, shoulders, and back. Declawing is both painful and traumatic, and it has been outlawed in Germany and other parts of Europe as a form of cruelty. Kangaroos are slaughtered by the millions every year; their skins are considered prime material for soccer shoes. Across the US, 6 to 8 million stray and abandoned animals enter animal shelters every year, and about half must be euthanized. In California, America's top milk-producing state, manure from dairy farms has poisoned hundreds of square miles of groundwater. Each of the more than 1 million cows on the state's dairy farms excrete 18 gallons of manure daily. Every year, the global leather industry slaughters more than a billion animals and tans their skins and hides. Elephants who perform in circuses are often kept in chains for as long as 23 hours a day from the time they are babies. Every year, millions of animals are killed for the clothing industry. An immeasurable amount of suffering goes into every fur-trimmed jacket, leather belt, and wool sweater. Neglect and abandonment are the most common forms of companion animal abuse in the United States. On any given day in the U.S., there are more than 65 million pigs on factory farms, and 112 million are killed for food each year. Every year, dogs suffer and die when left in a parked car- even for "just a minute" - parked cars are deathtraps for dogs. Dog owners: On a 78 degree F day, the temperature in a shaded car is 90°F, in the sun it can climb to 160°F in minutes. 98% of Americans consider pets to be companions or members of the family. For medical experimentation animals can be burned, shocked, poisoned, isolated, starved, addicted to drugs, and brain-damaged. Regardless of how trivial or painful animal experiments may be, none are prohibited by law. When valid non-animal research methods are available, no law requires experimenters to use such methods instead of animals. On average it takes 1,000 dogs to maintain a mid-sized racetrack operation. There are over 30 tracks in the United States. Female cows are artificially inseminated shortly after their first birthdays. Happy birthday! Birds don't belong in cages. Bored, lonely, denied the opportunity to fly, deprived of companionship... Many birds become neurotic in cages - pulling out feathers, bobbing their heads incessantly, and repeatedly pecking. According to industry reports, more than 1 million pigs die en route to slaughter each year. More than 100 million animals every year suffer and die in cruel chemical, drug, food and cosmetic tests, biology lessons, etc. Approximately 9 billion chickens are raised and killed for meat each year in the U.S. The industry refers to chickens as "broilers" and raises them in huge, ammonia-filled, windowless sheds with artificial lighting. Some chickens spend their entire lives standing on concrete floors. Some chickens are confined to massive, crowded lots, where they are forced to live amid their own waste. Neglect/Abandonment is the most prevalent form of animal abuse (approximately 36% of all animal abuse cases.) Cows are treated like milk-producing machines and are genetically manipulated and pumped full of antibiotics and hormones. Foie gras is made from the grotesquely enlarged livers of ducks and geese who have been cruelly force-fed. The best way to save cows from the misery of factory farms is to stop buying milk and other dairy products. Discover soy! A typical slaughterhouse kills about 1,000 hogs per hour. The sheer number of animals killed makes it impossible for pigs' deaths to be humane and painless. Because of improper stunning, many hogs are alive when they reach the scalding hot water baths. 13% of intentional animal abuse cases involve domestic violence. Animal cruelty problems are people problems. When animals are abused, people are at risk. Instead of improving conditions for animals, the dairy industry is exploring the use of genetically manipulated cattle. More than half the fur in the US comes from China, where millions of dogs and cats are bludgeoned, hanged, and bled to death. Millions of pounds of antibiotics are fed to chickens, who metabolize only about 20 percent of the drugs fed to them. The 3 trillion pounds of waste produced by factory-farmed animals every year is usually used to fertilize crops. Chaining dogs, while unfortunately legal in most areas, is one of the cruelest punishments imaginable for social animals. Tens of thousands of horses from the United States are slaughtered every year to be used for horsemeat in Europe and Asia. Since the last horse slaughter plants in the US were closed in 2007, thousands of horses have been shipped to Canada/Mexico. Abusers kill, harm, or threaten children's pets to coerce them into sexual abuse or to force them to remain silent about abuse. There are no federal laws to regulate the voltage or use of electric prods on pigs. Forty-one of the 45 state felony animal cruelty laws were enacted in the last two decades. In the United States, 1.13 million animals were used in experiments in 2009, plus an estimated 100 million mice and rats. As a result of disease, pesticides, and climate changes, the honeybee population has been nearly decimated. Many studies have found a link between cruelty to animals and other forms of interpersonal violence. Cows have a natural lifespan of about 20 years and can produce milk for eight or nine years. A fur coat is pretty cool- for an animal to wear. Eighteen red foxes are killed to make one fox-fur coat, 55 minks to make a mink coat. Fur farmers use the cheapest and cruelest killing methods available: suffocation, electrocution, gassing, and poisoning. In addition to diarrhea, pneumonia, and lameness, calves raised for veal are terrified and desperate for their mothers. During Canada's annual commercial seal slaughter, as many as 300,000 seals are shot or bludgeoned.

113 Facts About Animal Cruelty
113 Facts About Animal Cruelty
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Thank you for equipping yourself with knowledge. Help spread the word by sharing these animal cruelty facts!

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Thursday, November 22, 2012

The Biology of Muscle Growth

The sheer number of articles, opinions, magazines and experts on fitness and muscle growth makes the field of weight lifting appear more like the practice of medicine in the 16th century than a concrete science. Every day new theories, approaches and miracle workouts appear, contradicting each other and proclaiming that they have the truth, and that by following their advice you will achieve the body of your dreams. Clearly, some of them are on the right track and some are not, but how to tell the difference between them all? The answer lies in understanding the basics of the biological process of muscle growth. Once you know some key principles, you will be better equipped to evaluate whether a new exercise routine is based on sound physical principles-or completely bogus.

The most basic principle to understand is that your muscles adapt to whatever stress they are subjected to. If you spend all day on the couch, then you will be in possession of a fine set of muscles equipped for couch sitting. If you jog forty minutes each day, than your body will adapt to that. If you always follow the same number of reps and sets and routine when weight lifting, then your body will adapt to that too. And once you've adapted, your system will stop growing, and simply rest at this new plateau, having achieved the bare minimum required to function at that level. Therefore the basic idea is that if you want growth, you need to continuously overload your system.

The result of progressively overloading your muscles is called muscular hypertrophy, and that is the increase in muscle mass and cross-sectional area. Note that the number of muscle cells does not increase ( a phenomenon called muscular hyperplasia), but rather the size increases. As you work out, your muscles are subjected to microtrauma, where small tears appear in the muscle tissue. These tears signal what are called the 'satellite cells' on the surface of your muscle to activate and multiply and go to the damaged sites where they fuse with the existing muscle fiber, helping them regenerate.

The Biology of Muscle Growth

While the satellite cells are multiplying and fusing with the damaged areas, your immune system kicks in with a complex series of reactions that ultimately lead to inflammation meant to contain and repair the damage as well as clean up the area of waste products. This process if key not only to the health of the muscle, but its growth, as numerous hormones and cytokines are released which stimulate muscle hypertrophy. Among these are hormones like insulin-like growth factor (IGF), fibroblast growth factor (FGF) and hepatocyte growth factor (HGF). Growth hormone (GH) is also released, and is key to promoting satellite cell division and the release of IGF.

What is important to understand is that this entire process (microtrauma resulting in the complex interaction of satellite cells, the immune system, growth factors and hormones) is dependent not only on exercise, but also receiving the appropriate amount of rest and nutrition to optimize the healing process. Muscular hypertrophy occurs when the muscle heals itself, not when you are working out. Furthermore, your muscles will only adapt as much as they need to, resulting in a 'plateau' effect if you don't change things up and challenge them in new ways. This is why it is a good idea to switch up your exercise routines like they do in P90X, and always keep your body guessing as to what comes next.

The Biology of Muscle Growth
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Philip Tucker is a Fitness Product Review specialist for Miami based Extreme Fitness Results LLC. He enjoys keeping his body guessing with P90X's muscle confusion, a key principle of any P90X workout schedule.

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Monday, November 19, 2012

Why Do I Fart So Much? Find Out the #1 Cause of Excessive Gas & Farting!

There's a very common cause for people who have excessive gas & farting which most people are unaware of because most doctors are uneducated regarding it. If you frequently ask "why do I fart so much?" Then I have quite the surprising find for you as I'll explain the #1 cause of gas that you're completely unaware of. Best of all by eliminating this you'll also eliminate over 95% of all your other health complaints!

Why do I Fart So Much?

This epidemic is known as candida and it's a yeast that exists in essentially everyone. In some people it's a larger problem than in others, however the bottom line is always the same in that the same approach must be taken to be sure it is fully eliminated. This involves the use of natural anti-fungals, a strict anti-candida diet while also using nutritional therapy to boost the health of the body. This is enough to help eliminate the current overgrowth although without going after what created it in the first place you can never fully be free from it.

Why Do I Fart So Much? Find Out the #1 Cause of Excessive Gas & Farting!

Fortunately there are natural therapies not normally associated with candida which can allow your body to control it entirely on its own. 

How Candida Creates Gas!

Candida overgrows in the bowels by a process known as fermentation, now if you remember anything from biology back in school this process creates a lot of gas as a result. This gas needs to find a way out and quite often it's either through belching or farting, the latter being much more common. Quite often as well those who suffer from candida have issues with bowel obstruction as they don't always experience 3 bowel movements per day which will lead to a build up of waste in the colon, only making matters worse.

So what's the solution? Clear your bowel, clean out candida from the body while also doing natural therapies which will prevent it from ever causing problems again! 

Why Do I Fart So Much? Find Out the #1 Cause of Excessive Gas & Farting!
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Candida Making you Sick? Take our FREE Candida Test, Eliminate Gas for Good! by clicking http://www.howtocurecandida.com

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Wednesday, November 14, 2012

What Are the Best Male Enhancement Herbs?

A lot of people don't believe that natural herbs can enhance a man's sexual experience. But plants and herbs are responsible for hundreds of FDA-approved drugs and medicines. In fact, a recent study reported that over 60% of all cancer drugs come from plants. In addition, many herbs, including male enhancement herbs, have plenty of scientific support behind them.

So what are the best male enhancement herbs? It depends on whether you're looking for herbs that naturally produce testosterone, herbs that help sexual stamina, or herbs that increase blood flow throughout the body (including to the penis). Here are some examples:

Tribulus Terrestris--This ancient herb became popular after Eastern European Olympic athletes used it to enhance their athletic performances in the early 1990's. Tribulus accomplished this by naturally increasing the body's production of testosterone, a hormone that also directly affects sex drive and performance. Tribulus has also been shown to prevent premature ejaculation.

What Are the Best Male Enhancement Herbs?

Catuaba Bark--This herb comes from the Brazilian rain forest and enhances blood flow throughout the body. According to Michael van Straten, noted British author and researcher of medicinal plants, Catuaba is beneficial to men and women as an aphrodisiac, but "it is in the area of male impotence that the most striking results have been reported" and "there is no evidence of side effects, even after long-term use."

Maca Root--This Peruvian herb is known for increasing sexual stamina. The New York Times recently reported on a study that concluded that Maca is excellent for improving sexual staying power, reducing the possibility of prostate cancer, and improving male fertility. According to the Times, "peer reviewed studies published in the journal Reproductive Biology and Endocrinology backed up those findings."

There are many supplements that contain these male enhancement herbs, but quality is always an issue since the herbal medicine field is mostly unregulated. It's very important to find a reputable product that uses pure herbal ingredients. Of equal importance is the dosage, or amount of herbs used. But if you can get a hold of a supplement that uses high quality herbal ingredients in big enough doses, you'll most certainly see an increase in erection size, strength, and staying power.

What Are the Best Male Enhancement Herbs?
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Find out which male enhancement supplements use the highest quality herbal ingredients at Zenerx (or Zenerex [http://www.zenerexreview.com]).

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Sunday, November 11, 2012

Biology - Characteristics of Fish - An Introduction

Fish are vertebrate animals, that is, they all have a vertebral column or 'spine'. There are two main groups of fish, bony fish (Teleosts) and cartilaginous fish (Elasmobranchs). As the common names imply, the skeletons of teleosts are made of bone while the elasmobranchs have cartilaginous skeletons. The elasmobranchs comprise sharks, rays and dogfish which differ from teleosts in many respects. The teleosts are far more numerous, with a greater diversity of species than the elasmobranchs.

All fish are aquatic and breath by absorbing dissolved oxygen in the water using their gills. The bodies of both teleosts and elasmobranchs are covered with scales but those of elasmobranchs are spiky and project through the skin. This makes the skin feel very rough, like coarse sandpaper. The scales of the teleosts have a flattened, discoid shape and are covered by a thin layer of skin and mucus which probably reduces friction between the body and the surrounding water and makes them very slippery.

The swimming mechanism in both groups is very similar. A series of muscular contractions pass down each side of the fish alternately bending it from side to side and pushing backwards and sideways against the water. The water resistance exerts an opposite sideways and forward force on the fish. The sideways forces cancel each other but the forward force propels the fish forward. In both groups there are variations in this method of propulsion. Skates and rays make undulatory movements in the vertical plane as do flatfish like plaice. Some teleosts, such as the sea horse, propel themselves by undulatory movements of their dorsal fin.

Biology - Characteristics of Fish - An Introduction

In general, the fins contribute to stability and steering rather than propulsion. The median fins, dorsal and ventral, reduce the sideways thrust of the swimming movements and also reduce the tendency to roll from side to side. The paired fins help to steer the fish upwards or downwards through the water and contribute to turning and braking. The paired fins of elasmobranches are held in rather rigid positions while those of teleosts, with their flexible jointing to the body, are more versatile in their movements and can often be seen moving gently to keep the fish in a steady position.

In the teleosts, there is a swim bladder. An elongated, air-filled sac just below the vertebral column. This air bladder keeps the fish buoyant and prevents it from sinking when it stops swimming. The volume of the air bladder can be adjusted to compensate for changes in pressure at different depths. The elasmobranchs do not have swim bladders and so they start to sink if they stop swimming.

Although water is H2O, aquatic creatures cannot use the oxygen from this. The oxygen they breathe comes from the air which has dissolved in the water. There are four or five pairs of gills situated inside the mouth cavity. In teleosts, they are covered on the outside by a bony plate called the operculum. By movements of the floor of the mouth and operculum, the fish creates, a current of water which passes over its gills. Water is taken in through the mouth and expelled through the operculum in the case of teleosts, and out through separate gill slits in elasmobranchs. The gills are, in effect, finely branched, thin-walled blood vessels which, because of their multiple branches, expose an enormous surface to the water and so facilitate absorption of oxygen and loss of carbon dioxide.

Biology - Characteristics of Fish - An Introduction
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D G Mackean is the author of GCSE Biology, IGCSE Biology, and many other Biology text books. He has a site of Biology Teaching Resources at http://www.biology-resources.com which includes a bank of Biology Experiments for teachers, sample PowerPoint presentations, and many biological drawings

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Tuesday, November 6, 2012

Biology - Why Are Penguins Birds If They Can't Fly?

Everyone knows what a bird is, right? If I ask my seven-year-old son what a bird is, he'll respond with something like "a bird is an animal that has a spine, wings, two feet, hollow bones, and can fly." Or, if her remembers the little military chant his dad made for him, he might say, "hollow bones and scaly feet, feathered wings and goes tweet tweet."

Well, penguins can't fly. They have wings, feathers, two feet, and a spine, and they swim well but they cannot fly. Ostriches can't fly either, but both penguins and ostriches are considered birds. How is that possible? What's the deal?

It's all in the definition

Biology - Why Are Penguins Birds If They Can't Fly?

There's a difference between the common usage of the word "bird" and the scientific use of the word. The common definition is based on features of the animal you can see with your eyes and discern with your other senses like feathers, wings, number of legs, and being warm-blooded. My seven-year-old son knows the common definition of the word "bird."

Scientists use a slightly different definition.

Evolutionary birds

The scientific taxonomy of birds is a bit different than common usage. The scientific groups are made based on fossil evidence and other biological evidence such as DNA and mitochondrial DNA when the DNA can be obtained. Birds are in the Domain Eukaryotes, the Phylum Chordata meaning vertebrates, and the Class Avians. Avians have descended from theropod dinosaurs. More specifically, birds have descended from Archaeopteryx, which existed in the late Jurassic period.

Many scientists think of birds as the only type of dinosaur that didn't go extinct 65 million years ago. In fact, my daughter who is obsessed with dinosaurs, calls birds "tiny dinosaurs."

Scientifically, birds today are descended from dinosaurs, have feathers, a beak with no teeth, and they lay eggs with hard shells. Birds have a high metabolic rate, meaning they need to eat a lot to maintain their body temperature. (Some refer to them as warm blooded.) They have a four-chambered heart (like mammals), and they have lightweight, strong skeletons. Most birds can fly, but flying isn't a requirement to be a bird.

And that's the crux of it. The scientific definition of "bird" does not require the ability to fly.

Biology - Why Are Penguins Birds If They Can't Fly?
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Gwen Nicodemus is a freelance engineer/writer and a homeschooling mom. Visit her website, Notion Nexus, for unit studies, worksheets, notes, and educational videos.

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