Beech Bodies

beech

Take a walk in a winter forest and you can’t help but notice beech trees. Silky smooth bark and sand-colored dry leaves stick out like Christmas lights against a dull and gloomy background. While every other leaf drifted to the forest floor months ago, beech leaves hold tight like cat hair on a sweater.

It’s called marcescence – these leaves that just won’t drop – and it’s common in oak and beech (the trees are close relatives). But why keep the leaves? Are these trees just photosynthetic versions of hoarders?

One possible reason may be to protect that bud, the thin tapered structure often described as “cigar-shaped.” Inside the scaly covering are the beginnings of the new year’s growth. Hungry deer can ruin a tree’s plans for spring. But with beech trees, deer tend to get a mouthful of dry leaves whenever aiming for a yummy bud. (1)

What about attacks from smaller enemies? Insects seem to prefer infesting trees with leaves hanging on over winter.  R. Karban decided to yank all the leaves off a few dozen small oaks and compare infestation levels of a tree-noshing wasp. (2) His numbers indicate that wasps prefer leaf-hoarding trees three-to-one compared to his denuded ones.

I believe Nature is constantly sending messages of wisdom if we’ll just listen. In this case, perhaps she’s saying “every action has an upside and downside, but with diversity, there’s always hope for a better future.”

  1. Svendsen, Claus R. 2001. Effects of marcescent leaves on winter browsing by large herbivores in northern temperate deciduous forests. Alces 37(2): 475-482.
  2. Karban, R. 2007. Deciduous leaf drop reduces insect herbivory. Oecologia. 153: 81-88.

A Poinsettia by any other name… the cuetlaxochitl

poinsettias_jml

Politics was different in the early 1800s. You didn’t even have to run for office to be elected. Joel Poinsett’s friends nominated him to the South Carolina House of Representatives, and he won. By that time, he’d already completed years of travel through Europe, Russia, the Middle East, and South America where he’d met with foreign ministers, consuls, an empress, and many other political figures.

Within a few years, Poinsett became a U.S. congressman and then the first foreign minister in Mexico. That’s where he saw that plant that would later carry his name. He sent cuttings back to his greenhouses in Charleston and introduced the United States to a beautiful Mexican plant. Unfortunately, Poinsett got in a bit of trouble over his political views in Mexico (the word “poinsettismo” was coined as a result of his intrusive meddling) and was recalled from his post. Poinsett went on to cofound the National Institute for the Promotion of Science and the Useful Arts, later known as the Smithsonian Institution.(1)

Of course, the Poinsettia was well-known in Mexico long before Joel Poinsett. The plant is called cuetlaxochitl (pronounce), and grows as a shrub in Mexico City. The blood-red bracts are symbolic of sacrifices and creation.(2)

  1. To learn more about Joel Poinsett, read “Joel R. Poinsett: Versatile American” by J. F. Rippy
  2. Lots of interesting information about Poinsettias can be found at http://extension.illinois.edu/poinsettia/

Real Monsters – The Cockatrice

cockatrice_jlweb

In medieval bestiaries, entries portrayed the cockatrice as a rooster with the tail of a snake. It’s said to hatch from the egg of a cockerel that’s been brooded by a snake or toad. Often interchanged with the basilisk, only a weasel (or Harry Potter) can kill it.

cockatrice_manuscript

Wow. Crazy, right?  Maybe not so much.

Could poultry grow a snake-ish tail? Considering the evolutionary history of birds and embryonic development, yes. Birds are the last surviving descendants of dinosaurs, and early birds (evolutionarily speaking, not the worm-getting kind) had long tails. Over time, shorter-tailed members of the group prevailed as they flew unimpeded, and with better control, among brush and between branches. Vertebrae that once grew, fused as random genetic mutations delivered more successful flight. Genetically, just a few genes (possibly just one), activated early in development, control vertebral growth and tail elongation (1). So if you can stop that gene from turning on, you might just get a tail.

The second aspect of the cockatrice/basilisk story involved being born from a rooster’s egg. Now, that can’t be true – only hens lay eggs. Well, just like in humans, sex can be confusing. Primary sexual characteristics include sexual organs. In order to lay an egg, the bird would need an ovary. But most people identify hens and roosters by secondary sexual characteristics like coloration, size, and the presence of a comb and wattle. These traits develop because of hormones. If a female bird receives a dose of male hormone, she can produce rooster-like traits. This situation is actually not so rare. Because birds only use one gonad, a disease on the ovary would cause the other to develop. Since testes and ovaries develop from the same structure, the hen could get a dose of male hormone, producing rooster-like traits, and still lay an egg (2).

Brooding by a snake or toad wouldn’t help a chicken egg hatch. However, it’s not unusual to find a snake in a nest. Snakes of course eat eggs, and some birds even use snakes as partners to protect their nests from parasites or rodents.

As for death-by-weasel, the cockatrice/basilisk story is probably getting mixed with a cobra (3). The mongoose, which looks similar to a weasel, has an amazing cellular adaptation that makes them resistant to cobra venom. Many Greek and Egyptian stories (as well as the modern tale of Rikki-Tikki-Tavi) glorify the snake-killing abilities of the mongoose.

So next time you hear of a mystical beast that couldn’t possibly be real, give it a chance. And if you’d like to read more about the cockatrice and its devilish ties, visit awingandaway.

 

  1. Rashid DJ, Chapman SC, Larsson HCE, Organ CL, Bebin A-G, Merzdorf CS, Bradley R, and Horner JR 2014. From dinosaurs to birds: a tail of evolution. EvoDevo 2(25)
  2. Jacob J and Mather FB. 2000. Sex reversal in chickens. UFL-IFAS. FactSheet PS-53. http://ufdc.ufl.edu/IR00003037/00001
  3. Alexander, RM 1963. The evolution of the basilisk. Greece & Rome. 10(2) 170-181.

Saving the Corpse Flower… and its friends

corpseflower_fruits_animals

Deep inside the corpse flower are its developing fruits (painted in the sketch above). After 6-9 months, they’ll look like a column full of beautiful ripe tomatoes, tempting birds to eat them and distribute the seeds inside.

Unfortunately, both the corpse flower (Amorphophalus titanium) and its major seed distributor, the rhinoceros hornbill, are threatened by deforestation. Populations of the rhinoceros hornbill bird (Buceros rhinoceros) have declined by 72%. Other species, such as the orangutan and Sumatran tiger, are also suffering from this habitat loss.

What’s driving the deforestation? Many old growth forests in Sumatra have been cut to make way for palm oil plantations. Are the Sumatrans really eating that much palm oil? Nope. It’s you and me. So check your food labels – sometimes palm oil is listed under “vegetable oil” (if so, it must describe which plants). Look up eateries and food brands by using the Union of Concerned Scientists’ Palm Oil Scorecard – thankfully, Ben & Jerry’s has a good score!

The Corpse Flower Opens – and Stinks!

corpseflower_fri

Many flowers use insects to transfer pollen from one plant to another. Some flowers attract bees or butterflies. The corpse flower, though, uses carrion beetles and flesh flies. What attracts these pollinators? The color of decaying flesh, putrid scents, and the warm temperature of a freshly dead body. Lovely.

While we humans tend to focus on color, beetles and flies who pollinate the corpse flower may be more attracted to the scent and temperature. Angioy et al. (2004) showed that certain insects have the abilities to “see” temperatures and are attracted to heat. The heat generated by the spadix of the flower is unusual in the plant kingdom. Not many plants expend tons of energy to warm up to around 100 degrees Fahrenheit. Those few that do are called “thermogenic plants.” It’s generally accepted that the heat increases the range of the odors (Barthlott et al. 2009), which is true of course. But wouldn’t all plants benefit by increasing scent ranges? Yet this mechanism is found in plants that only mimic carcasses to attract pollinators – plants like the skunk cabbage and voodoo lily.

While most flowers give their pollinators a reward of some kind (think nectar), the corpse flower seems to just take, take, take. The plant mimics carrion, where pollinators normally lay their eggs, yet gives the pollinators no food or reward. Or could it?

I personally found it interesting that the spathe of the corpse flower closed back up after it bloomed. It’s probably protecting the developing fruit. Yet the fruit takes 6-9 months to mature. At the Chicago Botanic Garden, the spathe of their corpse flower wilted after about 3 months, exposing yet unripe fruit. Could the flower serve as protection for the developing carrion beetles? Is there any food supply for those youngsters when they hatch? Or is it just a dead end (pun intended)?

FYI: while other arums smell like corpses too (my personal favorite is the “pig-butt arum”), some species of Amorphophallus smell like bananas or carrots.

  1. Angioy AM et al. 2004. Function of the heater: the dead horse arum revisited. Proceedings of the Royal Society Biological Sciences. 271(3) S13-15.
  2. Barthlott W et al. 2009. A torch in the rain forest: thermogenesis of the Titan arum (Amorphophallus titanium). Plant Biology 11. 499-505.

The Corpse Flower, a Botanical Marvel

corpseflower_lupin_thuIt’s rare to see a corpse flower bloom. If you ever have the opportunity, take it… especially if you get to visit Sumatra. Lucky for me, a corpse flower (Amorphophallus titanium) blossomed in the greenhouse next to my office last weekend at NC State University (https://cals.ncsu.edu/corpse-flower-at-nc-state/).

It took the corpse flower, dubbed Lupin, 13 years to save up enough energy to bloom.  It’ll probably be another five years before it does so again. So corpse flowers are rather special. Actually, fewer than 200 cultivars have been recorded since 1889. But now’s your opportunity. For some yet unknown reason, a bunch are flowering at once (1).

Lupin grew six feet tall in under two months! That tall, purple-grey phallic structure is called a spadix. At its base are about 700 vibrant orange and purple female flowers and thousands of male flowers (2). When the one giant petal (actually a bract known as a spathe) opens, the spadix releases a stench to attract carrion beetles and flies who pollinate all those female flowers.

So actually, the corpse flower isn’t a flower at all. It’s over a thousand flowers wrapped into one giant, stinky, gorgeous inflorescence.

corpseflowerfemales

  1. http://www.sciencealert.com/no-one-really-knows-why-but-america-s-corpse-flowers-are-all-blooming-at-once
  2. Gandawijaja, D, S. Idris, R. Nasution. 1983. Amorphophallus titanium Becc.: a Historical Review and Some Recent Observations. Ann. Bot. 51:269-278.