Last week’s mystery creature, a very unusual looking bird, was the Hoatzin (Opisthocomus hoazin). Well done to six-year-old David who knew what it was. David is an avid animal lover who currently lives in Singapore.
Image credit: Bill Bouton, Image source: wiki commons.
Hoatzin are very unusal among birds for a variety of reasons and have intrigued scientists since they were first described in 1776, by German zoologist Statius Müller. Here are just some of facts about these amazing creatures.
Hoatzin are herbivores – but most of their diet consists of leaves, which is unique among birds. In order to digest this cellulose rich diet they have a digestive system more similar to cows (and ruminants) than to any other bird.
They have developed very large crops and the leaves they digest are fermented within their digestive systems. This process begins in their crop and is aided by anaerobic bacteria found throughout their guts, which feed on the leaves and help break down the tough cellulose within them.
They digest their food very slowly and are often seen sitting around, appearing to do very little at all.
The development of their large crop to aid digestion comes at a price; these birds have little space left in their chest and their breast-bones are very simple. Their pectoral muscles are small and weak. These are the muscles that power flight, so these birds are poor flyers and appear quite awkward and ungainly.
There is one other thing about their diet and digestion that makes these birds very distinctive, it is their smell! They are often referred to as Stink Birds, as the fermentation of leaves does not create an odour that humans find attractive. Because of this foul smell, people have no wish to eat them so they are not hunted. Sometimes it pays to be smelly!
Hoatzin live very social lives, often found in large flocks of up to 40 birds. They are found in the rainforests of the Amazon – usually in trees along a river or beside a lake or some other water source. They are very vocal birds with a variety of sounds from calls, to hisses, grunts and croaks.
The appearance of the Hoatzin is very striking and gives them the reputation as a ‘pre-historic’ bird. They have bright blue faces with dark red eyes. They have a strip of long feathers on their head, a crest, giving them a mohawk-type feature. They belong to the family called Opisthocomidae which comes from the greek for ‘have long hair behind‘ – referring to these mohawk styles.
Hoatzin are so unique among bird that they are the only species in this Opisthocomidae family.
The chicks of these birds have claws on their wings (wich disappear after about three months). If the nest is threatened the chicks will often flee and hide, they are even able to escape to the water if necessary and are good underwater swimmers. Once the coast is clear they will use their clawed wings to help them climb back up a tree, to the nest.
Based on their dinosaur-like appearance, and the wing claw of their chicks, there has long been a fascination with the evolution of this bird. Some thought they were the link between reptiles and birds. Others thought they were a modern day version of the Archaeopteryx, a bird attributed as an evolutionary step from dinosaur to bird. There were also similarities in appearance between the Hoatzin and the Archaeopteryx. Recent genetic sequencing of Hoatzin genome now suggests that it is the only surviving member of a lineage that branched off some 64 million years ago (not long after many dinosaurs became extinct) and that it evolved its traits indepedent of the archaopteryx lineage.
I found this one of the most fascinating Mystery Creatured to date, I hope you enjoyed it too. As always, if you have any suggestions for the Mystery Creature spot, please get in contact!
We love questions here at the Science Wows HQ; We generate a lot on a daily basis, and we answer many too. I was delighted to try out the new Facebook live tool for a Q & A session and got to answer lots of question sent in on all the STEM topics (Science, Technology, Engineering and Maths). Many of these questions were sent in by children, and, from the quality of the questions, and the inquisitive minds behind them, I am sure these are the STEM experts of the future.
If you sent in your question – thanks so much! If you want to send one in for another time then leave your question in the comments below or drop me a line.
Here is the video, if you missed it, or want to rewatch, I hope you enjoy and maybe pick up some new facts.
Here are all the questions asked; If you want to find the specific answer to that question in the video I have included how many minutes into the video it was answered. Under each question below is an additional fact, not included in the video… for some extra WOW!
Oran and Oscar wanted to know…
“Why is it blurry when you look underwater with goggles?” (1 min 20 secs)
Did you know that… if you get a really good pair of goggles or a scuba mask, then that extra air between the glass and your eyes will correct for the blurry vision problem and the light entering your eye will be bent correctly, allowing for a nice clear image? In fact, you may even see things clearer and larger – the mask can make things appear up to 33% larger and 25% closer!
and
“Why do crickets make that noise and where do they go during the day?” (5 mins)
Did you know that… crickets need warm weather to chirp, as they are cold blooded creatures. If the weather gets too cold they will not be able to generate enough energy for their normal chirps and their sounds will actually slow down or stop!
Elissa, Nia and Matthew asked …
“What are mosquitos for?” (12 mins)
Did you know that … the annoying buzzing sound we hear when a mosquito is near is the sound of their wings flapping at an amazing speed of 300 to 600 beats a second? That still doesn’t make the sound any more pleasant though, does it?
Photo credit: James Gathany (CDC)
Dermot is obviously an environmental thinker as he wanted to know …
“How do you convert wind power into electricity?” (11 mins)
Did you know that… humans have been harnessing the power of the wind for a very long time? The first windmills date back to 200B.C.
Ruairí had lots of questions, like …
“Why does your skin go brown after the Sun?” (17 mins 40 secs)
“Did you know that… the more sun exposure we get, the more the melanin producing cells move closer to the surface of the skin. We look like we are getting a darker tan but, more importantly, the melanin absorbed the harmful UV rays from the Sun, protecting our skin from damage.”
“What’s in the centre of the Earth?” (23 mins 30 secs)
Did you know that… scientists estimate that the temerpature of the Earth’s core is 6,000 Celcius? That is about the same temperature as the surface of the Sun.
“What’s inside a leaf?” (27 mins 30 secs)
Did you know that the colour changes we see in leaves in Autumn are due to different pigments inside the leaves? The colour we see depends on which pigments are present. Some pigments are more dominant than other so if they are present in the leaf they dictate what colour the leaf is. Some pigments we find in leaves are choropyl (green), Carotene (orange/yellow), tannin (brown) and anthocyanin (red/purple).
“What is inside a bird that helps it to fly?” (20 mins 30 secs)
Did you know that… some birds, such as ostriches, penguins and Emus are too heavy to fly? These birds (called ratites) are thought to have started out as flighted birds but have evolved flatter breastbones, shorter wings, weaker pectoral muscles and heavier bodies.
and…
“Why is fruit good for us?” (7 mins 30 secs)
Did you know that… tomatoes are actually considered fruit and that raspberries and strawberries are not true berries, but bananas are?
Emily asked…
“Why does your skin go wrinkly in the bath?” (4 mins)
Did you know… it takes five minutes of constant exposure to fresh water for the wrinkles to appear on our fingers, palms, toes and soles of our feet? It takes even longer when in sea water.
Amanda, from Spider Working, is a real lover of cats and she wanted to know…
“Why do cats have whiskers?” (24 mins)
Did you know that… cats are longsighted so their super sensitive whiskers allow them work out everything in their close environment with greater detail? This is particularly important when deciding when to pounce on their prey.
Did you know that… although monkeys like the sweet taste of bananas, they do not actually eat many in each day? Monkeys kept in captivity usually get no more than one banana a day, their diet is balanced with lots of other fruit, vegetables, seeds and nuts.
Cathal sent in a question while on holidays; he wanted to know…
“Why do you always feel cold when you get out of the pool, even though it is hot out?” (30 mins 10 secs)
Did you know that… the water that stays on our skin after the pool, or a shower, eventually evapourates into gas? To do this it need some heat energy, and some of this heat energy is taken from out bodies, making us feel extra chilly.
And finally, A question in from four brothers… Brendan, Liam, Iarla and Conor; these boys rescued a dying bumble bee by feeding it a sugar solution. They wanted to know…
“If the sugar thing really worked and why was the bee so shaky afterwards?” (28 mins 35 secs)
I really hope you enjoyed this, I’d love to do it again so please do share your questions for the next round and let me know what you think! Just pop your questions or feedback in the comments below.
Positive role models are always a great way to inspire the next generation. Ada Lovelace, the amazing programmer and mathematician is one such role model. The Ada Lovelace Initiative (A.L.I), named in her honor, is a community initiative set up to provide such positive role models, to highlight just how important, and able, women are in Tech and STEM.
Ada Lovelace – the original inspiration
Ada was born Augusta Ada Byron in 1815. Her father was the famous poet, Lord Byron and her mother was Lady Anne Isabella Milbanke Byron. It was her mother that would ultimately influence Ada’s academic advancement. After separating from Lord Byron she felt that an education was important for her daughter, to keep her mind engage and free from the mood swings she experienced in her estranged husband. Lady Anne arranged a series of tutors to teach her young daughter in the areas of language, mathematics and science.
From an early age Ada showed a flair for mathematics and languages. A meeting with the inventor Charles Babbage lead to a lifelong friendship and further access to academic teachings and theories and the time. It was while Ada was commissioned to translate an article on Babbages’ analytical engines that she added her own notes and theories and expanded the application of the machine into the realm of a real computer. Her works were published at the time but it was not until more than 100 years later that they were republished at the dawning of the modern computer. That is certainly a woman ahead of her time.
Ada is considered by many to have been the first computer programmers and a brilliant mathematician. She referred to herself as an analyst and metaphysician. Whatever title she held it cannot be denied that she is a wonderful role model in any era.
The Ada Lovelace Initiative – the modern day inspiration
The Ada Lovelace Initiative (A.L.I.) was set up in 2015 by Verify Recruitment. They responded to the startlingly low representation of women in the tech sector (only 25% of the STEM workforce is comprised of female professionals) in an inspiring way. They saw the strong and significant contribution made by the small number of women that do work in technology and realised what a valuable link they can be to the next generation. They set up A.L.I. in 2015 to bring these female role models right to the girls that need to hear their story.
A.L.I. connects female professionals working in technology with Transition Year secondary school students to present to students an insight into working in technology by telling their story. Women from the technology sector tell students about their educational background, their role type how they chose their career path.
In less than a year A.L.I. has reached approximately 3000 students in 14 counties in Ireland. The goal for 2016/2017 is to reach at least 5000 students in schools across the country.
By improving the information channels available to directly inspire girls to consider careers in this field, we believe that the role models can deliver invaluable advice and give the students a taste of the real-world of technology. Cathal Grogan, Director of Verify Recruitment.
There are already over 100 role models from 75 technology companies in Ireland registered as volunteers for The Ada Lovelace Initiative. Volunteers have registered from companies such as TripAdvisor, Udemy, Citi and Concern Worldwide to encourage young women to choose a career in technology.
One such mentor, Louise Bernstein, Senior Product Manager at ALTIFY had this to say:
“Today, no matter the career path girls choose – from chemical engineering to organising music festivals – tech will be in the background automating, speeding up, integrating, and uncovering new ways to achieve goals. Yet, less than 30% of women are involved in how that technology shapes their lives. I want to encourage more women to sit at the tech table, and be part of that future. By improving the information channels available to directly inspire girls to consider careers in this field, the voluntary role models of The Ada Lovelace Initiative deliver authentic career advice and give the students an insight into the real-world of working in technology.”
Photo: Louise Bernstein, A.L.I. Role Model with the 2016 Transition Year pupils of Rathdown School, Glenageary, County Dublin
For more information about the Ada Lovelace Initiative, to register your interest as a technology role model here or to register your school – please visit www.verifyrecruitment.com/ali
#AliMyStory is a voluntary initiative and the visits are provided free of charge to schools who would like to introduce a role model to their students.
Another week, another Mystery Creature; this one is fascinating. Some of its characteristics include being poor at flying and eating only plants (a herbivore), which is fairly uncommon among birds. This unusual bird also shares a feature with the prehistoric bird-like dinosaur called Archaeopteryx.
Do you know what that feature is and can you name the bird?
Remember to ask questions if you want help working out this week’s Mystery Creature… and check back at the end of the week to find out what it is and some amazing facts about this very unusual bird!
What did you think of last week’s Mystery Creature? An unusual looking fish, I’m sure you’ll agree. Did you guess what it was? It was a hairy frog fish (Antennarius species)!
These amazing looking creatures (some call them ugly but I think they look cute – in an ugly kind of way) come in various shapes and colours. Like this one…
They all have some distinctive facts in common, for example…
Frogfish tend to move slowly through the water, often they “walk” along the seabed, using their dorsal fins as feet, just like the epaulette shark, that featured here recently.
Many frogfish species have spiky structures all over their bodies, called spinules, which look quite like hairs. These can help protect them.
Frogfish like to blend into their surroundings, and they often hide in coral beds and in large patches of seaweed. Their ‘hairy’ bodies, help mimic these surroundings and keep them camouflaged. Some species are covered in algae, to further help with this.
Many species will also change the colour of their skin as another form of camouflage.
Frogfish are anglerfish, they have a little lure on the front of their heads, that acts like bait, attracting their prey in close enough for the fish to eat them.
They are prepared to wait for their dinner. Once they find a good place to hide they have been known to stay in that position for weeks at a time, until they manage to catch their prey.
Despite their slow movement and long waits in a stationary position, when they do strike to catch their prey, it is with incredible speed.
The wait is often worth it, as frogfish have large, extended mouths, and can catch and consume a creature as big as themselves. In fact, frogfish are carnivores and will even eat another frogfish if it comes too close.
It is not surprising therefore that they are solitary creatures.
Some species of frogfish can inflate, when threatened, similar to pufferfish, drawing in water to enhance their size.
Many divers and underwater enthusiasts can spend years waiting to spot one of these fish as they are so well hidden. They are certainly intriguing creatures. If you have any more information or facts to add, just pop them in the comments below. Or if you have a creature you want to suggest for the Mystery Creature slot, let us know!
So far this Irish Summer has been a bit of a washout. As I type, the wind is howling and the rain is sheeting down. We brave it when we can, and, when we can’t, we come up with indoor activities to amuse us. Sometimes though, there is nothing for it but to take out the blankets and turn on Netflix.
Here are some of our viewing recommendations this Summer. I’ve noticed a bit of a trend when comparing the adults choices to the children’s… both seem to include scifi, history and humour – not a bad mix!
THE CHILDREN
Scifi – the children were delighted to see Guardians of the Galaxy come to Netflix (this movie has a 12s rating) and it has already served them well as a ‘movie night’ option with friends.
Tech – We have introduced a bit more coding in the house this Summer, after a wonderful introduction from Galway’s Coderdojo classes. The children have loved the hour of code and have completed the Minecraft and StarWars challenges. This has sparked their coding imagination, and now they have found Gaming show (in my parents’ garage) they are completely hooked.
History – Horrible Histories is a constant entertainer in this house, even the adults have watched most of the episodes. It is amazing how the children are quoting historic facts, learned from the programme. When they finish the series they just start again from the beginning.
Humour – Apart from the giggles they get from Horrible Histories, the children are also loving the newest series of King Julien. I often pop my head in the room to find three laughing children snuggled on the couch.
THE ADULTS
Scifi – we stumbled across a scifi film called Push and loved it. It certainly deserves more than the three stars it currently has in the rating. The movie is about people with special powers, some can read minds, see the future, implant memories in people’s heads and move objects with their minds. And when the good guys and the bad guys have similar talents the story line keeps moving at quite a pace.
History – I am lucky if I get near the remote control these nights, since the second series of Marco Polo arrived on Netflix my husband has been binge watching. He is curious about the Mongol empire and enjoys the way the drama is portrayed.
Humour – The full second series of Better Call Saul is now available on Netflix. Although the plot thickens and the story gets a little darker, there is still plenty of the humour that so impressed us from the first series.
Image credit: Ben Leuner/Netflix
Regardless of what we watch, we usually round off the night’s viewing with a good belly-laughing episode of The Big Bang; It is consistently brilliant!
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Disclosure: As a member of the Netflix Stream Team I have received a year’s subscription to Netflix, free of charge, and an Apple TV, for streaming purposes. As part of Netflix Stream Team I will be posting regular updates on what we are watching and what is on offer. All opinions expressed are my own.
Inspirefest 2016 was a creative, innovative and diverse conference full of wonderful role models to inspire future generations in STEAM
I have just returned from an amazing event. If you have been anywhere near me in the last few days you will know how much this event has inspired me, moved me and changed me, because I have not stopped talking about it! The event was Inspirefest, and it certainly lived up to its name!
Through a series of wonderful and diverse speakers, the audience were entertained and amazed. We laughed, we gasped and we even shed some tears.
The event covered a wide number of topics over two days, from tech to fashion, to diversity, to finance, to communication and so much more in between. There is so much to talk about, to share, but I have decided to focus on one particular element – a subject close to my heart – inspiring STEAM in children of all ages.
WEARABLE TECH
We got an introduction to this from the onset, when Noel Murphy from Intel brought his two daughters on the stage to give us a musical demonstration using wearable tech. It is mind blowing to think that computing has shrunk so much that a tiny chip can be placed in clothing and jewellery, allowing us to perform tasks with the simple movement of our bodies. Aishling and Orla gave us all a bit of a laugh as they played music by simply moving their limbs.
Aishling and Orla helping dad, Noel Murphy, demonstrate some applications of wearable tech.
BEYOND 12
Alex Bernadotte shocked us with the revelation that we can predict, with a fair amount of accuracy, the life trajectory of an 18 month old child, based solely on their ZIP code. That is a very sobering thought. Only 9% of students from the lower income families will achieve a bachelor’s degree by their mid-twenties. We need to redress the balance. We need to make STEAM available to children regardless of sex, ethnicity, religion or social background. We need to provide support, inspiration and the right role models. That is why Alex set up Beyond 12.
Alex shared her own personal story of a life that began in Haiti and attaining her goal of a place in an Ivy league College. The reality, however, was that it got a lot harder from there, with no family experience of such a lifestyle; without personal role models and practical support, she really struggled to stay on track, physically, academically and emotionally. Beyond 12 was set up to bridge the gap between the education systems, to redress the balance of college attendance among lower income students and to provide real-life role models and support systems for those who do achieve these goals.
OUTBOX INCUBATOR
Throughout the conference, there were many examples of positive role model, perhaps none more so than Mary Carty, co-founder of Outbox Incubator. Mary really impressed us with her passion and drive. She noticed that, too often, STEAM was considered a ‘boys only’ club. She saw the amazing potential in so many young girls, so many of our daughters, our nieces, our friends. Together with Anne-Marie Imafidon, Mary stopped talking and started doing. She set up Outbox Incubator and last year, 115 girls from six countries came together to learn, share, inspire, create and find like-minded people, just like them. Girls like 13-year-old Niamh Scanlon .
EU DIGITAL GIRL OF THE YEAR (2015)
Niamh Scanlon took to the stage herself, and, with calm and confidence, shared what the outbox experience really meant to her. She told us about the apps she has developed… two so far… one to allow e-car owners locate the nearest available charge point and one for journalists, to allow them interview and connect with people in different time zones (with a video option included, what an amazing idea?). Listening to Niamh talk, I don’t think there is any doubt that all her innovative concepts will come to fruition through her own creation, determination, and optimism. It is clear, however, than Outbox Incubator has provided her with all the right tools for these, and future endeavours, as well as a strong and supportive network.
There are many more girls like Niamh – such as Edel Browne, Vanessa Greene and Elle Loughran, all of whom formed a discussion panel on the future generation of innovators. Our future is in good hands!
"The Next Generation" Panel (L to R): Edel Browne, Elle Loughran, Vanessa Greene, Mary Carty, Naimh Scanlon and Anne O' Dea
SOFT ROBOTICS
This one really made me sit upright in my chair. Dónal Holland of Soft Robotics Toolkit explained the latest developments in soft robotics and their medical applications. I liked it from the onset because Dónal showed us some soft robotics bases on balloons and simple plastic meshing (my kind of science!). What I really like about Soft Robotics is their outreach initiative… they have developed the Soft Robotics Toolkit, a free on-line resource allowing anyone develop their own soft robotic device.
But they didn’t stop there; they looked for feedback and when they realised that children were using this technology – they went back to the drawing board, adapting and innovating so that their information could be used with simple, available materials. They changed the tools in their toolbox. Now children all over the world are making robots with cardboard and glue; at this stage, I was practically bouncing on my seat.
This is amazing, this is inspiring… and this is what we will be doing this Summer!
“Innovation is a blend of creativity that exists in those that can see beyond what is currently available” Zoe Philpott, Inspirefest 2016.
POSITIVE ROLE MODELS
Brenda Romero from Romero Games gave a very entertaining talk. For the most part, Brenda drew laughter, but at one point she brought tears to our eyes. She told us how her daughter, as a seven-year-old, was told by a group of boys that she couldn’t play games… she was a girl! She had the perfect quip – not only could she play games very well, but her mother designed them! (What a perfect example of a positive role model for young girls.)
But this wasn’t what brought the tear to our eyes… Brenda showed us a card her daughter had made for her around that time, saying how she wanted to make a game with her mum one day. Then Brenda announced that her daughter, now 12, is going to be making that game this Summer with her mum, as a little project together. (I’ll pause while you go get a tissue!)
Brenda’s story made me think a lot about how my own children perceive the world; I’m a mother of two boys and one girl. I want STEAM to be available to all my children, and all children out there, regardless of age, sex, race, culture, demographic or religion. Do my kids think they can or can’t do things, just because of their sex?
I asked them!
Firstly, I shared the story of what the boys said to Brenda’s daughter when she was seven. Their jaws dropped (and I felt very proud of the fact that this shocked them all!).
Secondly, I asked them what they wanted to be when they grow up….
My daughter: an author and illustrator
My older son: a graphic designer and engineer who designs superhero characters
My younger son: same as his big brother… and a scientist
They certainly didn’t seem to see any barriers in the way of their aspirations and dreams. The only thing I realised after asking the question, was that my question was wrong; I was asking them what they want TO BE… but each of my children told me what they were ALREADY. My daughter has enough books written and illustrated to fill a library; my engineering son has folders full of superhero designs and my little scientist? Well, anyone who follows me on Facebook will know that he is always doing experiments, raiding my supplies and overshadowing me in our videos.
I will leave you with one last example of a positive role model, one that encourage kids to embrace individuality, enjoy their childhood and embark on meaningful adventures. It comes in the form of a doll. This doll is 18 cm high, she looks like a child… because she is for children! She can stand on her own two feet, because we all want our children to be able to do that. She can be anything she wants to be… an archaeologist, a ballerina, a kite-flyer, a superhero.
Her name is Lottie… and, inspired by a six year old girl called Abigail, she is the first doll in space. I’ll leave you with this video by Elena Rossini, telling Lottie’s story (you way want to reach for those tissues again).
For me, this sums up so much of what Inspirefest was all about – inspiration from the cradle up!
Disclosure: I received tickets to attend Inspirefest 2016; all opinions expressed are my own.
This question comes in from the very lovely, and very curious, Kayla, aged six, who can sometimes be found over at My little babóg blog. Kayla would like to know…
Where do tears come from?
Where do tears come from?
Tears are made by little glands above our eyes, called tear glands, or lacrimal glands. There is one gland above each eye; each produce tears that travel to the eye through tiny pipes, called ducts. There are a number of these tear (lacrimal) ducts behind our upper eye lids.
Our tear ducts are constantly producing tears, to keep our eyes clean and moist, but we don’t usually even notice. When we blink we wipe the tear fluid over our eyes, keeping them moist. This fluid is then drained off from the eyes through more ducts. It is only when we start producing a lot more tears that we start to notice them. The ducts that drain the fluid away cannot cope with all the extra tears and they start to run down our cheeks.
What are tears made of?
Tears are basically made of slightly salty water. They also contain enzymes that kill bacteria and vitamins and minerals. Some tears contain proteins, called hormones, that can change how we feel.
Why do we cry?
Scientists are still working this one out. We do know that we cry different kinds of tears in response to different things. Science defines crying as the process of producing tears in response to an emotion – be it sadness, fear, anger or happiness. When we produce tears to clear something out of our eye or to moisten the eye… Then we call this lacrimation.
So how does it all work? Well, the emotional crying seems to be triggered as a response to activity in a part of the brain called the hypothalamus. This part of the brain responds to our different emotions and can produce chemicals, called neurotransmitter, that will travel to specific parts of the body and induce a response. In the case of crying, the neurotransmitter produced is called acetylcholine and it triggers tear production in the lacrimal gland.
The reason why our brain responds in this way to emotions can vary. Babies, for example, cry to communicate with us… Telling us the are tired, hungry or in pain. This makes sense as they do not have many other forms of communication available to them. But why do we still cry here we are all grown up? It may be that crying creates other responses in our bodies, our heart rate changes, our breathing alters and other chemicals are released into the body. Crying can make us feel better.
Crying also allows us to show people how we feel! We may have evolved our crying mechanism to let people know what we are feeling, or to get sympathy or support.
Sometimes we cry when we see others hurt or sad and this created empathy, something that allows us build strong bonds and create supportive communities.
What different types of tears are there?
As I said above, we have three types of tears and they are…
Basal tears – these are the ones we produce to keep our eyes moist;
Reflex tears – we produce these in response to something else, usually something that is irritating our eye… From a small piece of dirt to a strong chemical, such as the vapour off a cut onion.
Emotional tears – these are the ones that get switched on by our emotions, even if we try to suppress them! These tears make us human!