Biology Newsletter #16

Biology Department Newsletter Issue 16: First half of Spring term, 2021

Spring is springing On one of my frequent walks today, I noticed the unmistakable signs of spring starting to appear around us. The snowdrops and crocuses beginning to flower, large clumps of daffodils appearing in parks and gardens, and the blue tits ferrying material back and forth to build their nest in the bird box on my garden wall (thank you Mr Hardman!). Spring brings with it renewed positivity, and the promise of longer and warmer days. It is a sign that there is much to look forward to and to be grateful for. As always, we want to encourage you to get out as much as possible and enjoy your outdoor spaces. This is especially important at the moment with the increase in screen time that comes with remote learning. Why not try to spot these spring flowers while you are out and about?

We’d love to see photos of the signs of spring that you notice on your walks so send them through to your Biology teacher and we can feature them in our next newsletter!

Biology Department Newsletter Issue 16: First half of Spring term, 2021

The RSPB Wild Challenge

Mindfulness

We hope that plenty of you heard Mr Coleman’s ‘call to arms’ to get involved with the recent RSBP Big Garden Birdwatch (see later), and that you identified some of our beautiful native feathered friends.

If you are now looking for your next initiative, why not try the RSBP Wild Challenge? There are a range of fun activities for you to complete, and depending on how many you do you can earn a Bronze, Silver or Gold award. The activities are divided into 2 sections: Help Nature and Experience Nature. Something fun to do with the family. Let us know how you get on!

RSPB Wild Challenge

Mindfulness is about paying more attention to the present moment, to become more aware of your thoughts and feelings. It has been shown to help us enjoy life more, to understand ourselves better and, importantly, to improve mental wellbeing. Those of you who watched ‘Winterwatch’ (BBC2) recently will have hopefully enjoyed the ‘mindfulness moments’ section of the programme where the sights and sounds of nature were played for 90 seconds, allowing the viewer/listener to just relax and ‘be’.

Why not give yourself regular breaks throughout the day to look after your mental health and connect with nature by listening to some of the sounds here.

Bad news for bees Did you know that in the UK we have around 270 species of bee, just under 250 of which are solitary bees which means that they tend not to live in colonies like the honeybee. Bees are amazing pollinators, being responsible for moving pollen between flowers, a process that is essential for fruit formation. Without bees we wouldn’t have a huge number of crops that we rely on such as apples, strawberries, tomatoes, peaches, peas, beans and broccoli, to name but a few.

In recent decades the numbers of many pollinating insects including bees have seen a sharp decline, which if not stopped could have a catastrophic affect on global food production. The recent reversal on a ban of pesticide use, which is thought to be at least partially responsible for bee deaths, is incredibly disappointing so the onus is on us to do our bit for the bees. Check out these links to find out how.

RHS

WWF

Wildlife Trusts

Biology Department Newsletter Issue 16: First half of Spring term, 2021

‘The Skylark’ with Mr Hardman Mr Hardman bookends his week by teaching Nature Appreciation to groups of 6th form pupils from both the Boys’ and the Girls’ School. What better way than to begin and end the week by having the opportunity to spread a passion for our natural world!??

The aim of this particular Enrichment Course is to teach pupils how to identify over 50 British Birds by sight, sound and ‘jizz’ (the way a bird moves across the ground or flies through the air). Another important component of the course is that students make a nest-box – there is something really magical about seeing nature interact with something made by your own fair hand, be it a bird table, a nest-box or a bat box (yes, we have those too at Habs – and they’re being used!).

Anyhow, I digress.

Picture the scene. Monday morning, Lesson 1. Mr Hardman introduces his Nature Appreciators to the first 20 British Birds. Slide 1…..easy! Blackbird. Slide 2….no problem!

Magpie!! Slide 3…….obviously, it’s a Robin!

And then we get to Slide 15. Silence.

“I’ll give you a clue!” says Mr Hardman, “It’s an annual school publication!”

This morning’s correct answer came from Mila, sister of Kielan – she’d seen her brother’s copy of Skylark sitting around at home.

And that got me thinking – why is the school magazine called Skylark? So I emailed Mr Llewellyn who delved into the school archive and told me that the school’s annual publication was first published in 1903. Originally called “The Skylark”, there was uncertainty as to whether the name would catch on.

Continued on next page…

Biology Department Newsletter Issue 16: First half of Spring term, 2021

‘The Skylark’ with Mr Hardman Having toyed with various names (“The Turtle Dove” and “The Raven” were swiftly discounted), The Skylark was settled upon. Turtle Doves, once numerous, are now on the Royal Society’s Protection of Birds’ Red List due to loss of habitat and food.

Skylarks are birds of open farmland and I count myself extraordinarily lucky to be able to hear their sweet song from my back garden. How do I know it’s a Skylark? The Skylark is well known for being able to sing continuously without a break for several minutes!

Whereas humans use just 2% of the air they breathe out to vibrate their vocal chords in their larynx to make noises (speech), Skylarks (and indeed all birds) use a syrinx through which they can sing and breathe continuously. Birds are able to utilise almost all the air from their lungs and can produce two different sound simultaneously, hence their rich and varied song.

Skylarks are ground nesting birds which makes their nests prone to predation: when danger lurks, Skylarks will try to draw the predator away from the nest site by dragging their wing on their ground, feigning injury. During the breeding season, Skylarks deliver their continuous song whilst climbing vertically towards the heavens to a height of 100m.

Very often, the onlooker can hear the Skylark, but will have to spend several minutes squinting into the sky, their faces upturned, searching for the the tiny black speck that finally gives away the bird’s position.

Skylarks are best known for their joyful, continuous song, delivered from the vertical display flight just described, and as the original school magazine naming committee concluded, “we have year in, year out, weather and hour permitting, a cherub aloft, pealing forth his desire to be one of us, just as our young spirits love to be like his, all brightness, joy and good feeling.”

At the end of Lesson 1, my pupils are well on their way to knowing their first 20 birds, so as part of their homework, I ask them to listen to the following piece of music: “The Lark Ascending” by Vaughan Williams. This piece immediately transports me to the shade of an oak tree, in the hazy afternoon midsummer heat, serenaded by the song of the Skylark. Please do have a listen. https://www.youtube.com/watch?v=ZR2JlDnT2l8

Biology Department Newsletter Issue 16: First half of Spring term, 2021

The Biology of love Sweaty palms, a racing heart, irrational behaviour.

Love is without doubt a complex and sometimes mystifying beast. For decades scientists have been trying to work out what love is. It turns out that the ‘Biology of love’ is more Chemistry, and whereas we usually associate love with the heart, it is in fact all about the brain.

A team of American scientists believe love can be broken down into 3 major categories (lust, attraction and attachment), with each stage being orchestrated by it’s own set of hormones, under the ultimate control of the brain.

Lust is driven by our need to reproduce in order to be able to pass on our genes to offspring, resulting, over a very long period of time, in the evolution of the species. The hormones oestrogen and progesterone are in control of lust, and are themselves released in response to signals originating in a part of the brain called the hypothalamus.

Attraction involves the ‘reward pathways’ that are triggered when we do things that feel good to us. The neurotransmitters (brain chemicals) dopamine and noradrenaline are released when we are attracted to someone, resulting in feelings of euphoria alongside the rather unfortunate side-effects of insomnia and loss of appetite. These two chemicals are also associated the ‘fight or flight’ response, hence the increase in heart rate and sweaty palms! Levels of Serotonin, a hormone involved with mood and appetite, are decreased.

Finally, and not to be underestimated, is the attachment stage of love, the most important component of long-term relationships, and the phase linked to the greatest intimacy, friendship, and parentinfant bonding. Oxytocin, the ‘bonding hormone’ is the key player here, and it is released from the hypothalamus in the brain.

HAPPY VALENTINE’S DAY! Source: Harvard University

Biology Department Newsletter Issue 16: First half of Spring term, 2021

‘What not to write in your Valentines card this year’ with Mr Lynch True monogamy is actually extremely rare in biology and is where both partners only mate with each other - some notable examples include (most) humans, prairie voles, seahorses, beavers, and scarlet macaws. The most likely explanation for this kind of system is the benefit to the survival and health of the offspring gained from males helping guard and rear them. The downside, though, is a marked decrease in the genetic diversity and ‘fitness’ of the offspring along with the dire consequences of poor mate choice.

Therefore, a form of social monogamy is much more common, with males and females forming a breeding pair, but engaging in what is politely called “extra-pair copulations”. Advantages to the male include increasing the survival chance of (probably) his offspring and genetic line and the female gains assistance in rearing/foraging and the chance to mate with genetically better males if the chance presents. On a side note, suggesting “extra-pair copulations” to your partner may be a tad risky, even with the biology behind you.

Prairie voles mate for life…

…as do scarlet macaws

If monogamy is not your thing then how about polygamy? Many examples exist in nature and can be split into polygyny - one male with multiple females - or polyandry – one female with multiple males. Two examples of polygyny are harems and leks. In a harem, a male will defend and herd his group of females and will compete with other males for control of it. Advantages to the male include the high likelihood of passing on his genetic information and the females gain protection for themselves and their offspring and sometimes the animal version of daycare. Leks are where males will group together to increase their chance of mating, usually associated with displays of fitness. Leks will attract more females than isolated males and so reproductive success for the males is increased.

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Biology Department Newsletter Issue 16: First half of Spring term, 2021

‘What not to write in your Valentines card this year’ with Mr Lynch For the truly free spirits amongst you, the third and final system may be more to your taste. In promiscuity there are no pair bonds and mating is random (although still subject to sexual selection). Genetic diversity is the main pay-off here, but it lacks all the advantages or pair/group systems so this strategy in usually found in very unpredictable environments.

Overall, the diversity of mating systems in animals is a fascinating example of the incredible variety of solutions that a complex evolutionary problem can yield. Just don’t bring up reproductive success on the first date.

‘Winterwatch*’ with Mr Coleman Helping nature through the winter Snowdrops spotted at HABS! Whilst out on one of my many lockdown walks, I was delighted to spot one of the first plants of the year to flower, the Snowdrop, blossoming in the grounds of our school. As I write this looking out of the window at snow falling and listening to an icy wind howling away, it is hard to believe that the soil temperature is warming up but I am now looking forward to spotting some more early spring flowers, such as crocuses.

Early spring flowers are particularly important for pollinators, such as bumblebees and some butterflies, which hibernate over the winter and rely on the source of nectar when they emerge. If you would like to see more colour emerge from your lawn this time next year then you will need to think about planting some bulbs ‘in the green’ come March/April time. More about this next issue.

Snowdrops, Galanthus spp.

Continued on next page… *in meteorological terms, Winter starts on the 1st December but astronomically speaking, it started on the solstice, December 21st. Of course, the natural world doesn’t recognise these specific dates and the signs of seasonal change are all around us if you get outside and notice them!

Biology Department Newsletter Issue 16: First half of Spring term, 2021

‘Winterwatch*’ with Mr Coleman Helping nature through the winter

Saaj, 8R2 Bluetit on fat balls

Mr Hardman in action

Vivaan, 7M

Goldfinches on a feeder

Felix, 7C

Arjun, 7C

Big garden birdwatch 2021 Over the last weekend of January, many boys and staff enjoyed taking part in the RSPB Big Garden Birdwatch by spending an hour counting the birds that they saw from their windows.

The Big Garden Birdwatch is the world’s largest wildlife survey and such ‘citizen science’ is so important because the more we know about nature, the better we can help to conserve it.

Mr Hardman did his best to inspire the lower-school boys with his assembly and blog and I rambled on about it as usual, to anyone who would listen! Some boys increased their chances by putting out a bowl of water and a small amount of crumbled bread, pastry or seed (but nothing salty).

Well done to everyone who took part, I hope that you enjoyed a quality hour spent discovering the wildlife on your own doorstep and thank you for sharing your photos, some of which can be seen below.

Please submit your results online by 19 Feb, or 15 Feb by post.

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Biology Department Newsletter Issue 16: First half of Spring term, 2021

‘Winterwatch*’ with Mr Coleman Helping nature through the winter ‘If a tree falls in the woods and there is no one around, does it make a sound?’

I will leave the answer to such philosophical questions to my learned colleagues in the T&P department but from first-hand experience, I can confirm that if you are in the vicinity then the sound and sight is truly something amazing if not a little scary.

Whilst out on another lockdown walk in a half-hearted attempt to keep fit, I pondered the more pressing poser of what on Earth could I write a few hundred words about for the latest Biology newsletter?

After briefly considering and ruling out a trip to an imaginary take-away pizza establishment, the answer literally came crashing down!

My true story takes place in Hadley Woods near the common a little way past the railway bridge. Walking as quietly and mindfully as I could amongst the deciduous woodland, I enjoyed the sound of a woodpecker and the brief sight of a deer when suddenly, I heard a tremendous cracking sound not far behind me. It was so loud that, at first, I feared a train crash but on turning back, I could see leaves in the air and branches on the ground. A large tree had fallen, luckily, just off the path and as the dust settled, a few folk suddenly appeared to see what the commotion was.

After a few minutes of milling around at a safe distance (2 metres!?) from the tree, I was none-the-wiser as to why it had fallen down and decided to do some research.

Now it turns out that the reasons that trees fall down are many and more complicated than any philosopher’s riddle.

Weather, fungal decay, restricted root growth, root damage, soil conditions, environmental change, type of species and height are just some of the possible factors that can cause a tree to uproot or break.

Therefore, my story ends here in a somewhat unsatisfactory manner and so I guess we will never know why this tree suddenly toppled much like the famous, thought experiment that I started with.

Next issue, in another exciting instalment of Mr Coleman’s ‘a funny thing happened on my lockdown walk’; I will ponder the role that Ursine mammals play in the Nitrogen cycle of the woodland ecosystem.

Continued on next page…

Biology Department Newsletter Issue 16: First half of Spring term, 2021

‘Winterwatch*’ with Mr Coleman Helping nature through the winter Insects: check out these amazing close-up bug photos!

The winners of the National Insect Week Photography Competition (see right) have been announced from the many thousands of entries from over 72 countries. Can you spot all six legs, wings (pair of) and the segmented body and jointed legs of these magnificent arthropods?

Weaver ants (India)

Like many such events and competitions, it is hoped that more people of all ages will take an interest in the subject and why not as it is estimated that insects make up over 90% of all animal life on planet Earth!

Stag beetles (Netherlands)

The winning entry – wasps (UK)

Poetry corner She Tells Her Love While Half Asleep by Robert Graves (1895-1985) She tells her love while half asleep, In the dark hours, With half-words whispered low: As Earth stirs in her winter sleep And puts out grass and flowers Despite the snow, Despite the falling snow.

Thank you to Mr Plotkin for this suggestion

Biology Department Newsletter Issue 16: First half of Spring term, 2021

‘Biology in the News’ with Mrs Oatridge Discovering of the world’s smallest reptile… and isn’t it cute!

Scientists think that they may have discovered the world’s smallest reptile, after finding two Brookesia, or ‘nanochameleon’ in Madagascar. With a body of just 13.5mm, the Brookesia nana male Brookesia is barely bigger than a seed. This makes it the smallest of all known species of reptiles (about 11,500 in total). Females are much larger at around 29mm. The Brookesia live in degraded montane rainforest where they hunt for mites and keep hidden in blades of grass. Commenting on the discovery, one of the researchers described the nano-chameleon as “a spectacular case of extreme miniaturisation”. Sadly, their habitat is under significant threat from deforestation and they have already been recommended for listing as a ‘critically endangered’ species.

Microplastics found in human placentas Around the globe, over 300 million tons of plastics are produced each year. With only 9% recycled, the threat from microplastics has been causing increasing alarm. This came to new heights last month when scientists detected their presence in the placentas of unborn babies. A team from Italy collected placentas from 6 women after they had given birth.

These were then dissolved and filtered revealing 12 small plastic pieces, each between 5-10 µm in size. As the team had only analysed 4% of the tissue, they predicted that the numbers would probably have been much higher. “It is like having a cyborg baby: no longer composed only of human cells, but a mixture of biological and inorganic entities” said lead scientist, Antonio Ragusa. Needless to say “the mothers were shocked”.

Summarised from ‘The Week’ and BBC news

Our Planet Now is a rich source of programmes, podcasts and articles looking at the environment, the challenges our planet faces, and what we can do to help it. Please spend a bit of time with half-term having a look.