Showing posts with label Curiosity Challenge. Show all posts
Showing posts with label Curiosity Challenge. Show all posts

Tuesday, May 24, 2016

Curiosity Challenge: Why Do Flowers Smell Good?

Allie W, Age 12


Dear Allie,

Flowers smell good and also look colorful for the same reason, to attract insects and birds. Flowers want these flying creatures to come visit them, so they can help them reproduce. Insects and birds spread the pollen and seeds of flowers to other ones, so they can be fertilized. This is also how flowers become fruit.

Beware, some flowers only smell good to some insects and in fact they smell foul to people. For example “Stinking Corpse Lily” and “Western Skunk Cabbage” smell just like their household name implies. These flowers want to attract flies, like the ones that you commonly see circling in garbage pails. They are very large and beautiful, but luckily not chosen for common yard ornaments!



Doris Glykys is a Principal Chemical Engineer at Amgen.  She's passionate about bringing lifesaving science to the people.

Sunday, April 24, 2016

Curiosity Challenge: Can Humans and Animals Understand Each Other?

Hey there, CSF fans, followers, and supporters!
Anna Bishop here with a cool Zoosemiotics (animal communication) question from Ella Nelson, age 11, who wants to know if humans and animals understand each other.




Excellent question! The answer is everyday and never: it depends on the animal, of course!


If you were to scold your dog for getting into the garbage, he might not understand all of your words, but he would know you were angry because of your face, voice, body language, and gestures. He might feel ashamed, because he knows it is something he should not do.


However, if you were to scold a chameleon, you might as well scold the wall. Chameleons, in the wild, do not communicate with one another, so their understanding of communication is essentially non-existent. They may be afraid of the loud noise, but they would not understand that you were trying to tell them something.


Communication is how we understand other members of our species, and work together. Most of the animals we can communicate with, communicate with each other in the wild. Take wild dogs, for example: they form packs, play, fight, and hunt with one another. It makes sense that they can understand people a bit. It is important for their survival to understand if other pack members are upset, excited, or in danger. Without a pack, wild dogs have a difficult time surviving, and if they did not pay attention to the feelings and needs of their pack, they might get kicked out of their pack, or left behind. They could die without a pack to protect him. So most dogs who were bad at communicating did not live to tell the tale.


There is also the complex idea of communication itself: we, as people, communicate mostly with spoken words and sometimes with hand symbols. We also observe body language: we can tell someone is upset just by looking at their expression and posture.


You’ve probably had a dog sniffing your face and legs. It may seem weird to you, but that’s how many animals communicate: smelling the bodies of other animals tells them important information like the age, sex, health, and even mood of other animals. Since we don’t use smell to communicate, we are different from many other mammals like dogs, cats, and rodents.


Interestingly, human communication with spoken words is most similar to that of dolphins, whales, and birds. These animals have languages and dialects. If a Costa Rican parakeet is surrounded by Amazon parakeets, the Costa Rican bird will change his own dialect to match those of the birds around him. The logic is, when in Rome, do as the Romans do!


Speaking of birds, have you heard of Alex the parrot? He was an African Grey parrot trained and observed in studies by animal cognition scientist, Irene Pepperburg. He was able to count, understand simple questions, and differentiate objects by shape and size. The fact that he was able to understand questions in a language invented by another species shows that parrots can do more than just mimic words. Here is a video of Alex with his trainer: https://www.youtube.com/watch?v=VZ2j1jOwAYU. Quite the brainy bird.


One African Lowland Gorilla, Koko, has become a celebrity for her amazing sign language abilities. She was able to tell us about her childhood in the wild, her father’s death, her desire to have a baby, and her love of kittens. Using a variant of American Sign Language (ASL), she can tell us what she knows and how she feels. She became best friends with Robin Williams, and told her keepers she was very sad when she heard about his death. This is a video of her with her teacher and friend of thirty years, Francine Patterson: https://www.youtube.com/watch?v=SNuZ4OE6vCk


Of course, Koko isn’t a pet, but she is still an animal that can have conversations with another species, while occasionally incorporating signs she knows by instinct. Here is a picture of her making common signs.


I shall end with another common animal companion: the horse. Horses communicate almost entirely through body language, and can tell if you are nervous, excited, or upset. They communicate with herd members by movements in their heads, necks, legs, and tails. When someone rides a horse, it is crucial that the rider and the horse have a decent level of trust, and at least one of them is experienced. Riders communicate to their horses how fast to go and in what direction, by gently pressing their legs into the horse’s side. Once the horse is well trained, he will respond to these cues appropriately. A horse learns to do tricks, like barrel turns and jumps, by paying attention to his rider's commands. In turn, the rider must recognize when the horse is tired, frustrated, and needs a break. A rider that ignores his steed’s body language is just as troublesome as a disobedient horse.

So hope that answers your question, Ella! Great to hear from you and stay curious about animals! Ciao for now!


About the Author: Anna Bishop is a sophomore at Sturgis Charter Public School and critter enthusiast. She is part of the Teen Advisory Board for the CSF, and her interests include zoology, zoo-psychology, ethology, raising insects, linguistics, and trying new recipes.

Wednesday, April 13, 2016

Curiosity Challenge: How do Cells Work?

Hi Jollie, thanks for the question. This is a hard question to answer because cells are so different from each other. Cells are specialized to do the job they perform. Nerve cells look completely different than liver cells and perform a different function within the body. Also animal, plant, and bacterial cells all differ from one another. To answer your question I’m going to focus on the general principles that enable animal cells to function.

Cells were initially discovered (observed) following the invention of microscopes in the 17th century.  Cell theory, stating that cells form the fundamental unit of life, was put forward over 150 years later. In the 20th and 21st centuries a major goal of biological research has been to understand how cells work, so that we can recognize what goes wrong in disease and how best to intervene to cure the condition. The working of individual cells can be summarized basically as follows:

1.     Proteins do the work of the cell. They perform the function of the cell whether that’s to send an electrical signal along a nerve fiber, or to detect invading pathogens as part of the immune system. These functions occur via enzymatic reactions that require energy.
The central dogma of biology,
which describes how DNA encodes protein assembly.
From NCBI Molecular Biology Reviews.
2.     Cells get their energy by converting sugars (glucose) into ATP (adenosine triphosphate) in specialized structures called mitochondria. ATP is a carrier of energy and it’s used in lots of different enzymatic reactions where its breakdown releases the stored energy and enables the reaction to occur.
3.     Where do proteins come from? Simply from DNA. DNA contains small units called genes, which provide the information or code required to tell the cell how to make proteins out of individual building blocks (amino acids). By turning on one set of genes and turning off another set of genes, cells acquire specialized functions so that a liver cell looks and functions differently from a nerve cell.



So we know a lot about how a cell works. But would it surprise you if I told you that only last month (March 2016) scientists reported the design of the first cell to contain the minimal number of genes that support cell growth and replication. Of the 473 genes required to generate the simplest cell, scientists know the function of only 324 of those genes. This synthetic cell was a bacterial cell and far less complex than human cells, which have approximately 20,000-25,000 genes. The Human Genome Project provided the full sequence of human DNA in 2003 (the first draft was released in 2001).  Since then, scientists all over the world have been trying to translate that information to identify all the genes in the human genome, the function of the proteins they encode, and how these genes are controlled, such as in the ENCODE project. This information will help scientists discover how cellular function becomes disrupted in disease and will hopefully provide the means to design targeted therapies to combat those conditions.

Find out more about the biology of cells and organisms at the Cambridge Science Festival!

  • Build Your Own Living Organism: Bioengineering for Everyone (two-day workshop) at the EMW Community Space, 934 Massachusetts Ave., Cambridge. Saturday, April 16, from 1-5pm, and Sunday, April 17, from 1-3pm.  Bioengineering allows us to speed up the evolution process!  Build your own living organism during this introductory two-day workshop for ages 10+.  Pre-register at http://bit.ly/1OPVVdR.
  • CELL @ Novartis Open House - Check It Out! at CELL@Novartis, 22 Windsor St., Cambridge, April 21st 1-4pm and April 23rd 10am-2pm. Through hands-on experimentation and minds-on problem solving, our programs aim to develop technical skills, build confidence, and open a world of possibilities for students to explore biomedical research and STEM.



--------
Karen Featherstone is a research scientist specializing in molecular and cell biology. Karen’s Ph.D and post-doctoral research investigated how DNA is regulated and how this determines cell function. 

Tuesday, April 12, 2016

Curiosity Challenge: How Can Lizards Regrow Body Parts?




You may know that some animals, such as reptiles and amphibians, can grow back lost body parts, but how do they do that?

Image via Wikimedia Commons

The process that allows animals, such as reptiles, to grow back their lost body parts is called regeneration. In order to understand regeneration, we must learn about DNA and gene regulation. Every living organism, from bacteria to plants, and including humans, are made up of cells. Cells are known as the smallest unit of living things. Cells are really small, and you need a microscope to take a close look at them. In fact, the human body is made up of trillions of cells! 

You may also know that DNA is called the genetic material in our cells. DNA stands for deoxyribonucleic acid, and it contains instructions for our cells. DNA is made up of nucleotides. We have four DNA nucleotides: adenine, thymine, guanine, and cytosine. The specific order of these nucleotides makes up our genetic material, and “packets” of DNA are called genes. You might hear that you get two copies of a gene, one from your mom, and one from your dad. Everybody’s DNA is different because we all have different copies of genes—this make us all unique!

Cells are the smallest units of living things. DNA is the genetic material in cells, and it is contained inside the cell's nucleus. DNA contains genes with instructions for our cells. DNA is composed of four different nucleotides, and the order of the nucleotides makes us all unique.
When lizards lose their tails, genes are turned on or off that allow them to grow back their tails. Scientists have discovered 326 genes important for tail regeneration. Some of these genes are also turned on during the development of the baby lizard (embryogenesis), and during wound healing. Scientists have found that genes in two complex signaling pathways known as Wnt and MAPK are important for lizard tails to grow back. These two pathways are important for making sure that cells are taking care of themselves. For example, when these pathways are not functioning properly, diseases such as cancer can occur.

Scientists believe that when lizards regenerate their tails, cells become “dedifferentiated.” This means that the cells near the injury become more like stem cells, and can be "programmed" to help grow back the tail. This process involves a lot of different genes, and regulation of these genes is what allows the lost body parts to grow back! Some genes are turned on, and some are turned off.

Being able to regenerate lost tails can be very helpful for lizards trying to escape predators. Lizards can control when to shed off their tails in a behavior known as autotomy. When a lizard feels it is in danger, it can shed its tail as a self-defense mechanism. The lost tail distracts the predator, and it allows the lizard to flee.

One thing to keep in mind is that limb regeneration takes time. The process can take weeks or months for lizards. Regeneration is a very interesting topic, but it is not just for lizards. For example, starfish can also grow back their arms!

Image via Wikimedia Commons
Although you may see lizards grow back their tails all the time on TV, scientists in real life are studying how lizards can regenerate their limbs in order to improve medicine! Hopefully this type of work can help scientists and doctors perform more advanced surgeries and discover better treatments for diseases.

Further Reading

--------------

Kenny Chen is a research assistant at MIT earning his PhD in Chemistry. He enjoys biomedical research and is curious about genes and biological processes.

Monday, April 11, 2016

Curiosity Challenge: How Were Animals Created?



Hi there CSF followers, fans, and supporters!


Anna Bishop here again, answering an awesome biology question from Ava Hartshorn, Age 7: How Were Animals Created?
( a picture of animal cells under a microscope)


Well, it all started about 575 million years ago, a time called the Ediacaran Period, when primitive animals began to develop. Lumps of cells probably weren’t what you were thinking of when you thought of animals! But lumps of cells created the first animals on Earth. There are three educated guesses about how this happened.

Sunday, April 10, 2016

Curiosity Challenge: Who Taught the First Teacher?

 
Great question Onasis. The most straight forward answer I can give is: their parents.

Teaching and learning in its earliest form would have occurred by imitation.  Our early ancestors would have imitated their parents, just like animals on nature TV shows imitate their parents' hunting and survival skills.  The acquisition of language and the generation and use of tools enabled the initial advancement of the human species from small groups of nomadic hunter-gatherers to larger agricultural communities, in what is termed the Neolithic Revolution. The benefit of agricultural food production to the individual health in these communities is not entirely clear.  But, ultimately, these communities supported larger populations. The development of larger communities led to the specialization of skills and roles within the community, for example farming, building, and trade. These communities developed into sophisticated societies with governmental structures, formalized ideology, and religion. The ancient Greeks and Egyptians are excellent examples of early human societies and how they were organized via class systems. The generation of writing within these societies drove the need for and development of a formalized education system.

In ancient societies most learning and teaching activities were between parents and children. Children would learn the trade of their parents and there wasn’t much opportunity to progress to different professions. The invention of writing (firstly from pictographic forms to the use of symbols in logographic forms) initiated the development of formalized learning environments. Archaeological evidence suggests that the Sumerians developed the first schools in what was Mesopotamia (an area that relates to present day Iraq, Syria, and Kuwait). The schools were associated with temples and were used to educate boys to become scribes and priests. A couple of centuries later, writing appeared in ancient Egypt, followed by the need for educated scribes. Scribes often followed their fathers into the profession, but there is evidence that boys from lower classes and girls could also become scribes. Formalized schooling of scribes was attached to religion and the temples. In both Mesopotamia and ancient Egypt, a student who made a mistake was physically beaten.

To find out more about how writing and the use of numbers developed, see the Cambridge Science Festival Blog - who created numbers and letters. 
You can also read more about the evolution of intelligence on the Cambridge Science Festival Blog - how did intelligence evolve over time.

Plato (left) pointing to the heavens and the realm of forms,
Aristotle (right) pointing to the realm of things.
From Encyclopaedia Britannica.
But who were the first teachers? Confucius (551-479 BC) is credited as being the first teacher. He was a philosopher, politician, and teacher in China. He wanted education to be broadly available and for teaching to be recognized as a profession. His philosophical ideas revolved around respect for family and ancestor worship, and are the founding principles of Confucianism, which is still influential in Chinese culture to this day. The ancient Greek philosophers Socrates (died 399 BC), Plato (approx 424-348 BC), and Aristotle (384-322 BC) are probably more famously recognizable as early teachers. Plato was a student of Socrates and founded what may have been the first higher education facility of the western world (Akademia). Aristotle attended Plato’s Akademia and, following Plato’s death, left to tutor Alexander the Great. He also founded a school called the Lyceum. All three men contributed greatly to western philosophy and Aristotle has been credited as being the founder of logical theory and the scientific method.


In America, it was the Pilgrims who established schools and introduced formal education in the 1600s. The Boston Latin School was the first public school in America (founded in 1635), and is the oldest existing school in the US.  Elementary schooling was not made compulsory in all states until 1918.

---------
Karen Featherstone is a research scientist specializing in molecular and cell biology. Karen enjoys mentoring early career scientists, but finds teaching tricky as she always has more questions than answers.

Saturday, April 9, 2016

Curiosity Challenge: Mucus!

Every year in the Curiosity Challenge we get questions about mucus.  Why do we get stuffy noses when we get sick?  What is that yellow stuff anyway?

Some of our friends have made a great video to explain it!  MIT alum, Thomas Crouzier (now assistant professor at the Royal Institute of Technology in Sweden), and Julia Co (now a postdoc at Stanford) wanted to share with the world their favorite material, mucus! With support from the Materials Research Society Foundation, and together with animator, Mair Perkins, they've created a short animation about how mucus keeps us healthy.

Check it out:





Thursday, April 7, 2016

Curiosity Challenge: “How Do Volcanoes Erupt?”

A spectacular eruption in Stromboli, Italy. Image via Places Under the Sun.
“Why Do Volcanoes Have Lava?” -- Alondra Sanchez, 6
“Why Do Volcanoes Erupt?” -- Darcy Baker, 6
“How Do Volcanoes Erupt?” -- Sara Solomon, 9
“What's In a Volcano?” -- Schnaubelt Baronvil, 10


A volcanic eruption is probably the most dramatic event that occurs in nature.  Imagine living next to a mountain that’s normally peaceful and calm.  Then, one day, the ground shakes, the mountain explodes, hot ash rains from the sky, and a wave of hot molten rock comes downhill--right towards you!  The giant clouds of ash belched up by the volcano block out the sun, sometimes for so long that the entire region’s climate changes.  It’s no wonder that most ancient cultures thought that volcanoes were controlled by gods.  We now know a great deal about volcanology--the science behind volcanoes--but we’re still in awe of these mighty features of the earth.


Monday, April 4, 2016

Curiosity Challenge: Who Created Numbers and Letters?









By Ben Tolkin

Great question, but it will need quite a long answer! You're asking about two of the most fundamentally human activities: language and mathematics. I'll start with letters.

Who invented letters?

For most languages, there wasn't just one person who “created” letters. (Though there are a couple of interesting exceptions I'll talk about at the end!) The letters we use for writing English and most European languages are slightly modified versions of the letters used by the Romans for writing Latin. Those were based on earlier Greek letters, which in turn came from even earlier ones... Almost every modern writing system is descended from just a handful of very early sets of letters.

Writing was developed independently in at least two places: the Fertile Crescent (modern-day Iraq) in 3000 BCE, and ancient Mesoamerica (Central America and Mexico) around 600 BCE. The development of writing in China in 1200 BCE was also probably independent, and its development in ancient India and Egypt may have been as well. Other than that, all parts of the world only started writing by borrowing it from their neighbors; Europe, Central Asia, and Africa had writing brought to them by cultural exchange, migration, or conquest.


The most basic method of writing things down is pictographic: to write about something, you just draw a picture of it. What makes it writing, as opposed to just making art, is when you start drawing not just objects, but abstract concepts represented by symbols. The earliest writing symbols used a mixture of pictures and symbols representing ideas. Let's say if you wanted to record that you'd traded a bull to someone for two chickens, you'd just draw a picture of a bull, two pictures of chickens, and some symbol representing a “trade”. As time passed, these pictures became more and more stylized, looking less and less like real objects. These scripts are known as logographic or ideographic writing systems; each symbol represents a word or idea.

This saves time (it's easier to draw a symbol everyone knows stands for “bull” than draw an accurate picture of a bull, every time) but it made the pictures hard to understand unless you'd been taught their meanings. If you look at very, very old artifacts, you might be able to make out some of the pictures, but later systems like cuneiform in the Middle East, hieroglyphics in Egypt, and bone script in China don't really look like pictures at all.

Akkadian cuneiform

Cursive Egyptian hieroglyphs

Chinese bone script


It's important to remember that for most of history, very, very few people could read or write. These writing systems had thousands of complicated symbols, but the only people who had to learn them were professional scribes. Being able to read and write used to be a full-time job!


Most writing systems today are not logographic (some Chinese characters are still pictures of the thing they represent, but most are not.) Almost every language instead uses a phonographic writing system, like an alphabet: each symbol represents a sound. (Other phonographic systems include syllabaries, where each letter represents a syllable, and abjad, where each letter represents a consonant.) While a language might have tens of thousands of words, they only have a few sounds, so alphabets are much easier to learn than logographic writing systems. So who invented phonographic writing?

Like many important inventions, it seems to have developed from interactions between different cultures. Ancient Egypt was a crossroads for many cultures speaking many languages, and Egyptian scribes needed a way to record all of them. One of these cultures was the Canaanites, a Middle Eastern group that spoke a language in the Semitic family (an ancestor of modern Hebrew and Arabic.) Egyptian scribes used a pictographic and logographic writing system called hieroglyphics to write their own language, but when recording the Canaanite language, they just used hieroglyphs to represent sounds: each consonant sound was represented by the hieroglyph of a word that began with that sound. For example, “house” was pronounced bayt in early Semtic languages (it still is in Hebrew today!), so whenever there was a "B" sound, scribes would just write the hieroglyph for “house,” a rectangle. The first letter of this alphabet was 'alp, a picture of a bull's head.


Believe it or not, those Egyptian hieroglyphics are the ancestors of the letters you're reading right now! 'Alp and bayt eventually turned into the Alphabet, and if you know what to look for, you can see traces of the original hierogylphs in letters today (don't think the letter “A” looks much like a bull's head? Turn it upside down!) The Canaanite writing system was the basis for Phoenician, a language spoken by sailors and explorers of the Mediterranean, who spread it to Greece; Greek writing inspired numerous systems on the Italian peninsula, that would eventually give rise to Latin, and the Roman Empire's conquests throughout Europe made it the dominant writing system on the continent. In the east, Phoenician was also an ancestor of Aramaic, which was the basis of Arabic; Arabic in turn became the basis for Persian and Urdu scripts used in Iran and Pakistan. Some suspect that Phoenician is also the basis of writing in India. Since Indian writing systems are used from Central to Southeast Asia, if this is true, it means almost everyone on Earth writes in a script descended from Phoenician.

This diagram shows how some major alphabets descended from Phoenician. The column in the middle is the Phoenician alphabet. To its left, you can see the letters of the Greek alphabet, and how they were based on Phoenician writing, and to the left of that, the Roman alphabet, based on Greek. On the right, you can see first the Hebrew alphabet, then Arabic.

That is a very brief history of how letters came to be. I haven't even talked about lowercase letters, invented in the Middle Ages to be easier to write with a pen. I encourage you to do more research on this fascinating topic, but do want to quickly discuss what I mentioned in the beginning: there are some cases where a single person did "invent" letters.

Many of these were still based on previous writing systems: Cyrillic, the alphabet used in Russia and much of Eastern Europe, was created a by a team of scholars and based mainly on Greek. The Armenian alphabet was developed by a single linguist around 400 AD, and seems to be based on Greek and Persian alphabet. In 1821, a Cherokee linguist named Sequoyah developed the first writing system for Cherokee, based on Latin letter forms.

Alphabets that are purely invented without previous reference are called constructed alphabets, and are usually made for fun, or as a work of art, like J. R. R. Tolkien's alphabets for his fictional Elvish languages. Sometimes, people construct alphabets because they think the current one is too confusing: the playwright George Bernard Shaw wanted people to use his Shavian alphabet, which he thought made more sense than the Latin one. There is only one example of a constructed alphabet being widely used for a real language, and that's Hangeul, the writing system for Korean.

This is a page from an early guide on how to read Hangeul. The simple, geometric shapes are the Hangeul letters, and the Chinese characters explain how to use them.

Chinese, in much the same way that hieroglyphics were used for writing Semitic languages; characters were used to represent sounds without much regard for meaning. Languages like Japanese adapted and modified Chinese characters to fit their language, but a Korean king named Sejong the Great decided that to promote literacy in his realm, he needed a perfectly logical alphabet completely suited to the Korean language. In 1443, a team of scholars assembled by Sejong completed Hangeul, a writing system that has been recognized the world over for its clarity and logic; each consonant represents the shape of the tongue in the mouth, while each vowel reflects the philosophical ideals of the kingdom. This makes Korean the only language with an alphabet completely unrelated to any other!


For more information on alphabets, you can check out Omniglot, an online encyclopedia of languages and writing systems. And to learn more about Egyptian hieroglyphics, look at this post on the Cambridge Science Festival blog!
------------

But what about numbers? We're not finished yet!

The simplest way of recording numbers is a unary system, in which each mark (a numeral) represents an object being counted. The number two? Two marks. The numbers seven? Seven marks. This system is easy to learn and understand, and very sufficient for writing small numbers. The trouble comes when you want to record a number higher than humans can easily count. Writing down two hundred marks isn't just tiring, it takes just as long to read as to write; you can't tell at a glance the difference between two hundred markings and two hundred and ten.


Still, this system is still widely used for counting small numbers; around the world, people use different kinds of tally marks to keep score in games. And believe it or not, unary numbers were the basis of the most popular number systems in the West for over a thousand years: Roman numerals. Though there are a couple of fancy rules involved in Roman numerals to make them shorter to write down, the principle is the same as any unary system: to read the number, add up the numerals. X is ten, V is five, and I is one: XXVI is ten + ten + five + one = twenty-six.

Learning to read Roman numerals can be cool if you want to translate inscriptions on old buildings, but it's not very useful in the modern world. Like all counting systems based on a unary model, it's hard to use with high numbers; the highest symbol in Roman numerals is M, for a thousand, so any number of multiple thousands will take a long time to write. Addition and subtraction are pretty easy, but multiplication is a chore, and division is... well, I'll include a link explaining division at the end, but let's just say it's no fun. These days, we use a
positional number system instead.

In a positional system, you don't just add up each numeral; the position of a numeral affects its value. We write twenty-six as 26, the numeral 2 followed by the numeral 6. But because of the 2's position, we know it doesn't really mean "two," it means "twenty": two times ten. Who invented this system?

Like writing, positional numbers were likely invented in two separate locations: both ancient Chinese and Indian civilizations used similar positional number systems. However, the Indian system was more comprehensive: the Indian mathematician Brahmagupta was the first to treat the numeral zero as a number like all the rest, and it is this system that forms the basis of our modern writing system. Ancient Indian mathematicians had a tremendous impact on math: algebra, trigonometry, and negative numbers were all perfected during the Golden Age of Indian mathematics, from roughly 400 to 1600 CE.

Numeral systems from around the world, all based on the original Indian numbers


But while Indian cultures used a positional number since at least 700 CE, it wouldn't spread to Europe until the Middle Ages. The person most associated with Indian numerals in the West is mathematician Leonardo Bonacci, or Fibonacci, who introduced the new system of writing numbers to Europe in 2012. He had learned the numerals from traveling about the Mediterranean and meeting Arabic traders, who had learned it from the studies of Persian mathematical genius al-Khwarizmi. For this reason, the numbers used in the West are sometimes called "Arabic numbers," even though Arabic-speaking countries call their numbers "Hindi numbers."

Again, this is an extremely brief summary! I didn't even mention some of the most interesting writing systems in history, the Babylonian and Mayan systems! You may not have thought that such a simple question would take so long to answer, but that's the strange thing about the history of science: sometimes the most simple ideas take the longest time to establish. The alphabet and numerals we use today seem perfectly natural to us, but they were created by complicated and messy cultural changes. It's one of the reasons history is so interesting: you get to see the weirdness hiding behind everything we see as ordinary.


For more information on numbers, there's no better resource than Isaac Asimov's Asimov on Numbers (ISBN: 067149404X). To learn how to divide using Roman numerals, start with mathematician Lawrence Turner's page here.
--------

Ben Tolkin once spent a summer teaching himself Elvish. His recommended strategy for learning important things is to ask the questions so obvious no one can think of an answer to them.