Skip to content

Nature

The hunting leech

by Ines Morales 01 Nov 2011
The hunting leech

Leech via Shutterstock

If you're an urban dweller like me, you have probably never seen a leech up close and personal. If you're a dedicated movie fan, you have probably seen them often in old adventure movies, almost invariably latched on to the back of a screaming damsel in distress or a harried hero as he or she emerges from a dismal swamp in some far off country. Leeches, unfortunately, are not well treated by the film industry. It's a real shame, because they are far more interesting than that.

For instance, did you know that leeches hunt down their dinner in very ingenious ways? A leech's diet is very narrow, in a certain sense. They feed on blood, which is why they are frequently used for medicinal purposes. Young leeches always go for fish and amphibians and then, as they grow up, switch to mammals. If you're a fish or an animal, and you go past a leech, it will see your shadow and know exactly where you are. Even if you try not to cast a shadow, the leech will notice you by sensing the disturbances in the water as you move. Either way, you will be dinner. Leeches' hunting methods are quite effective.

rainforest deforestation.

Montage of a leech using shadows from waves passing overhead to find its prey; Credit: California Institute of Technology

As it turns out, according to recent findings from a team of Caltech researchers, leeches' hunting methods are also quite thoughtful. Apparently, when young leeches see shadows and sense movement at the same time, they tend to pay attention to both - and I imagine they get somewhat scrambled in the process. Adult leeches, however, do the reasonable thing and concentrate on the disturbances in the water, which are more reliable than the shadows.

According to the scientists, the more mature strategy of adult leeches has nothing to do with physiological changes. Their bodies are just the same as when they were young - at least for the most part. What happens is that adult leeches are more capable to evaluate their different hunting methods and choose the one best suited to their current circumstances. In other words, leeches watch, practice, and learn as they grow up. Good news for the leeches, but maybe not so good for us. More and more, natural sciences are demonstrating that our "superior" intelligence is not unique to humans at all.


Trending Eco-Friendly Clothing

Love My Planet Women's Relaxed Fit Hoodie
Earth
Quick Add
Close
Notify me
Notify me
Love My Planet Women's Relaxed Fit Hoodie
Love My Planet women's eco-friendly relaxed fit hoodieSize Guide Centimeters 8 10 12 14 16 18 Bust 84 88 92 97 103 108 Waist 66 70 75 80 85 91 Hips 91 95 99 104 109 116 Bust: Measure around the fullest part of...
£38.00
£38.00
Close
Notify me
Notify me
Penguins Hate Push-Ups Men's Pullover Hoodie
Earth
Quick Add
Close
Notify me
Notify me
Penguins Hate Push-Ups Men's Pullover Hoodie
Penguins Hate Push-Ups men's eco-friendly pullover HoodieSize Guide Centimeters XS S M L XL XXL Height 171 175 179 183 189 195 Chest 86 93 99 104 116 129 Waist 71 76 81 89 99 112 Chest: Measure all round your chest just below...
£38.00
£38.00
Close
Notify me
Notify me
Lightning Bolt Kids Long Sleeve T-Shirt
Earth
Quick Add
Close
Notify me
Notify me
Notify me
Lightning Bolt Kids Long Sleeve T-Shirt
Lightning Bolt kids eco-friendly long sleeve t-shirtSize Guide Centimeters 3-4yrs 5-6yrs 7-8yrs 9-10yrs 11-12yrs Height 98 112 125 136 147 Chest 60 66 70 75 84 Chest: Measure all around your chest just below your armpits. Height: Your natural height If you fall between...
£18.00
£18.00
Close
Notify me
Notify me
Notify me
Union Jack Tote Bag
Earth
Quick Add
Close
Notify me
Notify me
Union Jack Tote Bag
Union Jack eco-friendly colour tote bagProduct Specification Organic Cotton Tote Bag. Twill Weave (170gsm). 37 x 42 cm (7cm gusset.) Made in India / Designed on the Isle of Wight. Wash Cool, Hang Dry.
£16.00
£16.00
Close
Notify me
Notify me
Prev Post
Next Post

Eco-Friendly Shop

Women's Clothing

Eco-Friendly Clothing for Women Our online shop offers a wide range of sustainable women’s clothing products, including t-shirts, hoodies, vests, sweaters, shorts, and...
Shop Now

Men's Clothing

Eco-Friendly Clothing for Men Our online shop offers a wide range of sustainable men’s clothing products, including t-shirts, hoodies, vests, sweaters, shorts, and...
Shop Now

Kids Clothing

Eco-Friendly Clothes for Kids Our online shop offers a wide range of sustainable kids clothing products, including t-shirts, hoodies and jumpers. Our garments...
Shop Now
Someone recently bought a
[time] ago, from [location]

Thanks for subscribing!

This email has been registered!

Shop the look

Choose Options

Earth Times
Sign up for exclusive updates, new arrivals & insider only discounts

Recently Viewed

Edit Option
Back In Stock Notification
this is just a warning
Login
Shopping Cart
0 items

Before you leave...

Take 20% off your first order

20% off

Enter the code below at checkout to get 20% off your first order

CODESALE20

Continue Shopping