Stories from the Rainforest

Yara

Tom — Mon, 14 May 2012 12:21:48 +0000

When I walk in the rainforest, I marvel at the philodendrons and find it relaxing how they cascade down the trunk of a tree like a green waterfall. Cougar in the young adult stories also finds philodendron peaceful, except for this night in a new story: Magic River.

“It’s getting dark. I see a small beach over there,” Cougar said and pointed toward the bank. JJ maneuvered the canoe and Cougar hopped out to pull the canoe on the beach. Without talking they both cut woody vines and drank fresh water inside the vine and continued their routine of JJ starting a small cooking fire and Cougar fishing.

Cougar retrieved his fishing crossbow from the canoe and loaded a bolt. The light was dimming as he approached the bank five minutes up river. It was hard to see smaller fish but a large disk-shaped shadow caused ripples near some river reeds. Paca, he said to himself. Cougar grinned and swallowed saliva thinking about the sweet, light flavor of the fish. He aimed, squeezed the trigger, and pulled the thrashing twenty pound fish to shore. While picking up the fish, the water where he shot the pacu caught his attention. It was pink, then red, then purple. He dropped the fish and collapsed into a sitting position. Cougar felt his heart race, exacerbated by short, shallow breathing. The intensity of the light grew as it went through the cycle: pink, red, purple; pink, red, purple. He struggled to get up, but his legs quivered. Cougar closed his eyes. Not seeing colors, he gained strength to get up and picked up the fish with his back to the river.

Cougar approached camp. JJ looked up and Cougar stared through him. “Wow, that pacu must have put up a fearsome fight. You look pale and stumbled into camp,” JJ said. Cougar nodded and helped JJ prepare and put the fish over the fire to roast. They were silent. The sizzle, snap, and smell of the cooking fish didn’t stimulate conversation. JJ stared into the fire. Cougar watched the light of the fire flicker on the large leaves of a philodendron enveloping a giant tree next to them. Usually, fire light showing the philodendron was soothing to Cougar. But tonight, he saw the vine turn pink, to red, to purple.

Cougar tapped JJ on the shoulder. “JJ, tell me the legend of the Yara.”

Let’s Have a Party

Tom — Wed, 09 May 2012 15:46:32 +0000

Philodendrons like to throw a party for their pollinators, beetles. The fleshy stalk (spadix) contains fertile male flowers at the top, a zone of sterile male flowers in the middle, and fertile female flowers at the bottom. The middle zone of the spadix heats to 35 degrees Celsius (Wikipedia online. “Philodendron”, accessed April 25, 2012) to start the party. That’s hot! The hot zone of the spadix also releases pheromones to attract male beetles. They hone in on the sweet, fruity smell. At first, the male beetles fly in the general direction of the irresistible smell, but when they detect infrared radiation from the spadix, they fly like heat-seeking missiles. The males enter the spathe surrounding the spadix followed by the females. The party is on. The heat speeds up the mating and gorging on the party treats, pollen and sterile male flowers loaded with lipids. After a day of frolic the males leave covered with pollen, looking for the next party.

Comments welcomed, Thomas.

Home Jungle

Tom — Fri, 04 May 2012 13:50:27 +0000

When I take a walk in the woods near my home I expect to see two plants in the Arum family, skunk cabbage and Jack-in-the-pulpit. When I take a walk in the rainforest I’m overwhelmed by Arums. The primary pollinators of Arums are flies and beetles. Since it doesn’t freeze in the tropics, flies and beetles are active all year and the Arum family of plants can reach their full expression. The Ceiba people in Stories from the Rainforest live in an area, just east of the Andes, where the Arum family is the third richest in the number of species. A group (genus) of Arums covers the trunks of many trees. JJ, in the stories, sits on a platform in the canopy contemplating under the spell of the cascading green leaves of these Arums. I have a member of the Arum group JJ enjoys on my desk. I also look at the leaves, which seem to flow and find myself relaxed. You may have this house plant from the rainforest, a philodendron. In the rainforest a philodendron germinates on the forest flood and sends out a tendril seeking the shade of a large tree. After finding the tree, the tendril will climb and attach to the tree by aerial roots. The philodendron grows and grows, encircling the trunk. After established it ceases to be rooted in the ground.

Like butterflies, philodendron leaves in the rainforest go through metamorphosis. The seedling leaves are small and heart-shaped; then, they morph into larger juvenile leaves; and when the vine reaches the canopy, or pencil-thin aerial roots reach the ground, the juvenile leaves morph into large adult leaves. When you’re a climber this strategy makes sense. You want less weight while ascending and large light catching leaves when you get there. I wonder if my heartleaf philodendron on my desk would go through leaf metamorphosis if it was in the rainforest.

Comments welcomed, Thomas.

Jack

Tom — Thu, 26 Apr 2012 00:59:26 +0000

After my visit with the skunk cabbage on my last walk, I started to look for another early spring flower in the Arum family. The pattern of the Arum family is tiny flowers clustered on a fleshy stalk (spadix) often inside a hard modified leaf (spathe). The flower I was looking for did have a spathe that looks like a pitcher with a floppy lid. Although in the same family as the skunk cabbage, it did not stink if a leaf was broken. To my delight I found several jack-in-the-pulpits (Arisaema triphyllum). I just call them jack.

Jacks can’t produce a “stinky” odor so they use a “slippery wall” strategy. After a fly investigates the jack’s flower chamber, including walking on the flowers and thus pollinating, the fly tries to escape. Just above the flower chamber in the spathe there is a ledge or gap that allows escape. The fly struggles to get up the slippery wall, again and again. Some don’t make it to the ledge or gap. They slide back down for the last time and become part of the corpse litter at the bottom of the flower chamber. The irony is, the decomposing fly now produces the odor that attracted him to his death.

Hitch-Hikers

Tom — Fri, 20 Apr 2012 15:26:10 +0000

Carrion beetles, who gets excited about carrion beetles? I must admit I’m interested in creatures whose job it is to recycle in an ecosystem. The American Carrion Beetle (Necrophila ameriana) may be fooled by skunk cabbage but will find a “stinky” decomposing carcass. The female beetle lays her eggs near or on the carcass and the eggs hatch in a few days. The larvae feed on the carcass and pupate in a cavity excavated in the ground. Let’s go a little deeper into the ecology of the carrion beetle. They have hitch-hikers, wingless mites traveling with them. When the beetle lands on a carcass, the mites drop off and eat the eggs and larvae of flies thus, reducing competition for the beetle’s larvae. The mites hop back on when the beetle gets ready to take off to find another carcass. The beetles and mites have a mutual relationship, they both benefit.

Other hitch-hikers I wrote about the picture book Grandmother Sloth are sloth moths. Sloths go to the ground once a week to discharge their dung. They use their stubby tail to dig a depression, deposit their dung, urinate on it, and cover it with leaves. During this process, sloth moths, living in the fur of the sloth, fly to the dung, lay their eggs, and fly back up to the sloth. The eggs hatch and the larvae feed on the sloth’s dung. This is a commensal relationship. The moths benefit and the sloth is not helped or harmed. Hitching-hiking, amazing, how in the world did this strategy come about?

Grandmother Sloth: how she got her smile, hard copy available on Amazon.com, dedicated and signed copy available on this web site.

See you next week. Comments welcomed, Thomas.