Pining for Carbon

Conifers_landin

The boreal forest, or taiga, extends across Canada and Russia. Conifers dominate this cold ecosystem. The evergreen needles allow the trees to photosynthesize all year.

While conifers grow well in the frigid taiga, they don’t decompose very quickly when a tree falls. In other habitats, trees that die release their carbon as they decay. The pines, firs, spruce, and larches of the taiga soak in carbon from the atmosphere, add that carbon to their mass, and hold it in their bodies even after they die. One study suggests that the boreal forest sequesters twice as much carbon as tropical forests and six times the amount held in temperate forests (1).

For now, the taiga is helping us combat climate change. As temperatures warm, though, stored carbon can break down and release into the atmosphere as carbon dioxide, exacerbating the issue. The more we limit carbon emissions now, the more the boreal forest can help us into the future.

  1. https://www.borealbirds.org/sites/default/files/pubs/report-execsummary.pdf
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Playful Kittens

3kittens_Landin

Play. It’s well-documented in many mammals and birds. Fish have also been observed leaping over sticks and batting around balls.  Frogs play-wrestle and tadpoles ride bubbles. Turtles play tug-of-war (1). Some invertebrates even play. Octopuses, and possibly spiders and wasps, have shown play behaviors too (2).

Welcome to our new playful kittens, adopted from SAFE Haven.

  1. Burghardt, G.M. 2015. Play in fishes, frogs, and reptiles. Current Biology. 25(1) R9-10
  2. Zylinski, S. 2015. Fun and play in invertebrates. Current Biology. 25(1) R10-11

 

Homegrown Squash

squash_landin

These heirloom varieties of squash are the literal fruits of my springtime obsession with Cucurbits (the gourd family – almost 1000 species of zucchini, pumpkin, watermelon, cucumber, etc).

This obsession grew thanks to Dr. Lori Shapiro who knows the coolest facts about squash! For instance, before domestication, wild gourds contained bitter toxins. Only megafauna like mammoths could ingest and disperse the seeds of these protected fruits (1). In the Americas, early hunter-gatherers used dried gourds as floats for fishing nets and to hold food and water. They also used fresh wild gourds for the medicinal properties of the bitter compounds (2). The wild gourd (Cucurbita pepo) was the first plant domesticated in the Americas, and the first agriculturalists likely grew them for their nutritious seeds rather than the bitter flesh. Thanks, Lori!

  1. Kistler, L., L.A. Newson, T.M. Ryan, A.C. Clarke, B.D. Smith, G.H. Perry. 2015. Adaptive domestication in squashes and gourds. Proceedings of the National Academy of Sciences, 112 (49) 15107-15112.
  2. Hart, J.P., R.A. Daniels, C.J. Sheviak. 2004. Do Cucurbita pepo gourds float fishnets? American Antiquity. 69(1) 141-148.

 

Limes & Science Go Together

Landin_limes_web

In 1740, an English commodore led an ill-fated squadron of ships out to sea, prepared to circumnavigate the world (and attack some Spanish holdings along the way). Of over 1800 men starting the voyage, only 500 survived. The main killer was not war or weather, but  nutrition.

Just a few years after the flotilla returned, a naval doctor conducted one of the most famous experiments in the history of science. After a few months at sea, sailors on Dr. James Lind’s ship began exhibiting signs of scurvy. The doctor treated sick sailors with random supplements to their regular diet. Some shipmen received vinegar, or sea water, or barley water. They made no improvement. Sailors who were given citrus fruits, though, made quick and full recoveries.

Unfortunately, dogma and a small sample size caused many (including Dr. Lind) to underestimate the power of citrus. It wasn’t until the mid-1790s, as scurvy-free anecdotes and experiences grew, that ships rationed out citrus juice to prevent the disease. Enjoy some lemons, limes, or oranges in celebration of science!

Beech Bodies

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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/

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.