Why Are Cactuses Spiky?

<p>What makes a cactus a cactus? And what are you supposed to call a group of these plants--cacti, cactuses, or cactus?! We'll find out in today's episode, as we learn more about the cactus family with Kimberlie McCue of the <a href="https://dbg.org/" rel="nofollow" target="_blank">Desert Botanical Garden</a> in Phoenix, Arizona. She'll answer kid questions about why cactuses are spiky and how they got those spikes, as well as why teddy bear cactuses aren't actually cuddly!</p> <p><em>Download our learning Guides: <a href="https://www.vpr.org/sites/vpr/files/202102/why_are_cactuses_spiky_.pdf" rel="nofollow" target="_blank">PDF</a> | <a href="https://docs.google.com/presentation/d/1Y4OpkeUjeWThYsQtrIGib0RNWusGCg-xuFnX42VrGro/copy" rel="nofollow" target="_blank">Google Slide</a> | <a href="https://www.vpr.org/sites/vpr/files/202102/but_why_145-cactus-transcript.pdf" rel="nofollow" target="_blank">Transcript</a></em></p> <p>Those prickly spines that are so characteristic of the cactus family are actually modified leaves! Cactuses don't have the kind of leaves like a maple or oak tree. But they might have had leaves that were at least a little more like that way way back in the past. Over time, those leaves evolved into the spiky spines we see on cactuses today because they help the plants survive in hot, dry environments.</p> <blockquote> <p>Why are cactuses spiky? -Noah, Iowa</p> </blockquote> <p>"They can be a defense mechanism to discourage herbivores - animals that eat plants - from eating the cactus. But, also, spines create shade!" explains Kimberlie McCue.<br> <br> "When you're covered in spines, as the sun moves across the sky, those spines are casting shadows on the body of the cactus. They're little shade umbrellas!"<br> <br> All cactuses are native to desert environments, and some live in places where it never rains at all. So how do they get water to survive? Well, Kimberlie tells us that these plants grow not too far from the ocean.</p> <p>"Early in the morning, there will be fog that comes off th