March is the longest month of the school year. The winter holiday breaks have passed and spring recess is weeks away. Glances outside the classroom window show lingering grey skies, but with hopes of a sunny spring on the horizon.
You could brighten things up by making your science class festive for the upcoming St. Patrick’s Day on March 17th . Maybe go "old school" by dying carnations to teach about xylem and phloem…or jazz up the lesson by making daisies photoluminescent. That’s not my style, though. I prefer a more off-beat holiday tie in.
St. Patrick's Day is celebrated to honor the missionary who converted Ireland to Christianity and who rid the country of snakes during the 5th Century A.D. According to legend, the patron saint chased the slithering reptiles into the sea after they began attacking him during a 40-day fast he undertook on top of a hill. As it turns out, there are not any snakes in Ireland…but there are two critters that look a lot like snakes. They are the common or viviparous lizard (Zootoca vivipara) and the slow worm (Anguis fragilis).
Have a Class Discussion About Organisms’ Adaptations to Earth’s Environments:
The common or viviparous lizard (Zootoca vivipara) is Ireland’s only native species of reptile. It gives birth to live young, a rarity in the reptile world, where most species lay eggs in order to reproduce. The common lizard lives in bogs, coastal sites, and grasslands. It is about 13 cm long and hunts invertebrates like insects, spiders, and snails. Scientists believe it arrived in Ireland within the last 10,000 years.
The slow worm (Anguis fragilis) has an elongated round body about 50 cm long, a pointed head, and no legs. It is called a worm; it looks like snake; but it is a species of legless lizard. It is thought to have been introduced to Ireland in 1970 from Britain. Slow worms eat invertebrates such as slugs and worms and are generally found under rocks and logs or in compost heaps.
Address the Claim about St. Patrick and the Snakes!
St. Patrick could not have been a snake whisperer! Ireland is one of only a handful of places worldwide—including New Zealand, Iceland, Greenland, and Antarctica—that has no snakes. In fact, there are no fossilized remains indicating that snakes ever existed in Ireland.
The most recent Ice Age ended 10,000 years ago. During that period, it was too cold for snakes. After the Ice Age, snakes could not reach Ireland since it is an island. Britain was connected to Europe by a land bridge 6500 years ago. There are three snake species there. Ireland, however, lost its land bridge to Britain 2000 before. Bears, boars, and lynx were able to migrate to the Emerald Isle, but snakes were not.
St. Patrick was not a snake charmer or serpent wrangler. No fossils. No land for snakes to migrate across. Inhabitable climate. There is not evidence to support the claim that St. Patrick gave orders to snakes.
So, What Gives with St. Patrick and Snakes?
Serpents are symbols of evil in the Judeo-Christian tradition. Genesis portrays a snake slyly convincing Eve to eat fruit from the Tree of Knowledge of Good and Evil, despite explicit instructions against such action. In Greek Mythology, the Gorgons have hair made of venomous snakes, and looking upon them turns the viewer to stone.
Serpents are also linked to practices of heathens. Heathens were polytheistic early pre-Christian peoples who lived in the lands around what is now called the North Sea. They performed ritual sacrifices of animals to gods, elves, and ancestors. The sacrifices were done to honor the gods or to gain their favor for specific purposes such as peace, victory, or good sailing weather.
St Patrick converted many non-Christians / heathens to Christianity. They are the metaphorical snakes. (You could work a little English and History into this lesson!) Here are two links with more information about St. Patrick:
S-S-S-Speaking of Snakes
It would be unwise for someone to release their pet snake in Ireland. Alien species present a risk to well-established fauna. The isolated nature of an island population makes Ireland highly vulnerable to an introduction of a non-native species. Here is a link about reptiles in Ireland:
It looks like a snake…
If you do spend some time talking about legless lizards in your class, consider using the “Do Now” 4 New Legless Lizards Discovered in California. As with other Life Science "Do Nows" & "Exit Tickets", students generate context-based guesses to fill in the blanks of a reading selection. This is intended to be a tie-in to the classification and evolution units, but, as you can see, it could also be used for St. Patrick’s Day!
Serpents (snakes) and legless lizards look similar but are only distantly related. If you trace their evolutionary history back far enough, snakes and other legless lizard species all descended from lizards, but after they split into two different groups, the different groups each lost their legs independently. This means that while snakes are legless lizards, not all legless lizards are snakes. Spotting a legless lizard might be an unusual happenstance…..or Luck O’ The Irish.
Gertrude Katz has spent over 30 years teaching K-12 public school students all major subjects. She has taught biology and education at the college level. The majority of her career has been spent instructing biology at the secondary level.