Karpechenko, Polyploidy, and Other Long Words

Greetings, everyone! It’s the second Saturday of the month already, and I am delighted to be here talking about one of my favorite science topics with you. As you may know, or may have guessed from reading my blog and noting the disproportionate amount of genetics posts, I am a genetics major, major DNA nerd, and plant biology minor. I’m going to bring all those things together in this post, so hold on to your hat and let’s have some fun!

As with many of my science posts, our topic today stems from a class I am taking (Evolutionary Genetics of Plants, in this case). My teacher told us a story, which I thought was cool, so I am now going to repeat it to you.

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The story was about this guy.

The guy in the picture above supplies the first of the long words in this post: his name, Georgii Dmitrievich Karpechenko. As you may have guessed, he was Russian. Specifically, he was a Russian botanist and plant cytologist (cell biologist) who did some interesting experiments with plant breeding. Let’s explore them.

Presumably, Karpechenko enjoyed both cabbages and radishes, or else he just wanted to contribute to improved agricultural productivity in his nation of limited farmland, or possibly both. Either way, he wanted to create a plant that produced a cabbage in the shoot and a radish in the root. The logical way to do this (his reasoning presumably went) was to cross a cabbage with a radish.

Here we have to back up a bit and get into some more long words. Cabbage and radish are different species, but not only that, they are in different genera (the first word of a scientific name); cabbage is Brassica oleracea and radish is Raphanus sativus. Usually, the definition of a species is “a population which is reproductively isolated (i.e. can’t breed) from others.” Of course, the only thing in science with no exceptions is that everything has an exception, and Karpechenko was indeed able to breed his cabbage and radish (for reasons we haven’t talked about in class yet) and produce a hybrid plant.

Well, unfortunately for Karpechenko, his hybrid didn’t look anything like either a cabbage or a radish. It was just a weed. Worse yet, it was a sterile weed; it produced seed pods, but no seeds. Fortunately for botany and genetics, though, Karpechenko didn’t give up on his experiments just yet. He kept observing his plants and noticed one day that a branch of one of them was producing seeds, even though the rest of this plant continued to be sterile. Furthermore, when he planted the seeds, they gave rise to fertile (if weedy) plants, and a new head-scratcher: how could this be?

Backing up again: The fertility of plants (or any organism, really) arises from a special cell division process called meiosis, which some may have learned about in high school biology. Most organisms are diploid, that is, they have two complete sets of chromosomes. For example, humans have 23 chromosomes in a set, and a total of 46 chromosomes in two sets. It works the same way for cabbage and radish; each has 9 chromosomes in a set, and 18 chromosomes total. This comes from reproductive biology; in any diploid organism, one of the sets of chromosomes comes from each parent. So in order to reproduce, plants (and animals, and fungi) have to produce haploid gametes, “sex cells” with only one set of chromosomes apiece. (In humans, we know them better as the sperm and the egg.) This is what meiosis is all about.

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A summary figure of meiosis. Note the homologous chromosomes separating into different cells; don’t worry about the different colors.

 

In order to reduce the chromosome set number, or “ploidy,” from diploid to haploid, chromosomes line up in matched (“homologous”) pairs and separate into two new cells (see the figure above). These cells then undergo further division to form gametes, the details of which we won’t worry about.

Now let’s think about Karpechenko’s sterile hybrid. This little weed had one set of chromosomes from cabbage and one set from radish, which enabled it to grow and function. However, when it came time for meiosis, it turned out that radish and cabbage chromosomes were different enough that they wouldn’t pair and divide into different cells, and no gametes were formed, which ultimately meant no seeds.

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Karpechenko’s experiments shown as seed pods. “Amphidiploid” is the same thing as tetraploid.

 

So what about that branch that became fertile? Well, it turns out that plants sometimes spontaneously undergo whole-genome duplications, in which, just as it sounds like, the entire genome of the plant is duplicated in the cell. (This happens routinely before cell division, but then it all divides into two cells. In whole-genome duplication, what happens is that the cell thinks it’s divided, but actually hasn’t, and now has four sets of chromosomes rather than two.) This happened in Karpechenko’s plant, in a branch precursor cell, and gave rise to a tetraploid branch, having four sets of chromosomes, two from radish and two from cabbage. Now, suddenly, all chromosomes had homologs to pair with in meiosis, and seeds could form.

Karpechenko had discovered polyploidy, the state of having more than two chromosome sets, which turns out to be a rather important phenomenon in plants. Besides generating greater genetic diversity, helpful to plant breeders, polyploidy results in more DNA, bigger nuclei, bigger cells, and eventually, bigger, more robust plants overall. It’s so useful that plant breeders sometimes induce polyploidy with chemicals to help in developing new varieties. Many important plants, such as wheat and canola, are polyploids.

What happened to Karpechenko himself? Well, in the early 20th century, the Soviet Union’s leadership was not big on genetics. In 1941, Karpechenko was arrested on a false charge and executed, but not before making a major contribution to botany and genetics.

What do you think? Have you heard of Karpechenko before? What about polyploidy? (Isn’t it cool?) Do you have any questions? Tell me in the comments!

Edible Biochemistry: The Health Benefits of Chocolate

Hello, everyone! It’s the second Saturday of the month, time for a short science post. Since Valentine’s Day is coming up on Tuesday, and chocolate is a popular gift (and who doesn’t like getting it?), I thought I’d talk a bit about some biochemistry of chocolate’s health benefits. There’s a bit of organic chemistry involved here, so bear with me.

Chocolate, even dark chocolate, which is 35-85% cocoa, is a very complex substance. Like any plant-based substance, it is “choc” full of different complex organic compounds. These include polyphenols, which are just compounds with multiple benzene rings.

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This is benzene. Each corner is a carbon with two hydrogens attached. It’s not as scary as it looks. 🙂
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This is catechin, found in chocolate. Again, each corner is a carbon. Don’t worry about the details of the structure, but do note the two benzene rings–this is what makes it a polyphenol.

 

Yay for chemistry class! Now back to chocolate. Some polyphenols found in chocolate, similar to the catechin molecule shown above, have antioxidant properties. You’ve probably heard this already; a lot of healthy foods, including blueberries as well as dark chocolate, are advertised as having antioxidants.

But what is an antioxidant? What do they do, and how is that beneficial to human health? Well, antioxidants are simply molecules that scavenge free radicals. This begs another question: what is a free radical? Free radicals, like the methyl radical below, are just chemical species that have an unpaired electron. They are highly reactive and go around stealing hydrogen atoms from other molecules, including (one of my favorites) DNA. So the punch line is that free radicals can be damaging to important biomolecules like DNA, and have thus been implicated in cancer, aging, and other human health issues.

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The methyl radical.

You can see how antioxidants, like those found in chocolate, can be beneficial to human health by removing free radicals from the body’s cells and reducing radical-induced DNA damage. So, yes, chocolate really is good for you. (Of course, it can still contain copious amounts of sugar, so the key, as with everything, is in moderation.) What a great gift for Valentine’s Day or any time!

What do you think? Do you like chocolate? Have you heard about antioxidants but wondered what they do? Tell me in the comments!

The Synthetic Biology Equation: Engineering + Bioscience = The Future of Biotech

(Perhaps that title is a bit audacious; I don’t claim to be able to predict the future of anything. But it’s entirely possible that synth bio will play a big role in biotech in the future. Let’s explore that more below. . . .)

Good morning, everyone! I was traveling last week, which prevented my putting up this post on Saturday as usual, and I decided to postpone it till today.

One of the classes I took last semester was Biotechnology and Society, and I decided to write my final paper on synthetic biology after the teacher mentioned the first production of a self-replicating “man-made” cell by a group of scientists in California.

Before I dig into that a bit more, though, let me define synthetic biology (or synth bio for short): it is the full-scale application of engineering techniques to biological systems. How is it different from regular genetic engineering/GMO production, then? The answer lies in the scale of said engineering: for genetic engineering, it’s on the gene level, one or more genes plus regulatory elements (regulating the expression of the gene) within an organism. For synth bio, though, engineering is on the level of an entire chromosome or even a genome, either wholescale editing or rewriting from the ground up. Essentially, synth bio is genetic engineering on steroids.

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Stephane Leduc, author of La Biologie Synthetique

 

A little history: Synthetic biology was first conceived, if not put into practice, way back in 1912 when Stephane Leduc, a French scientist, published La Biologie Synthetique. In this book, Leduc stated that the consistent and controlled reproduction of natural processes seen in other sciences, like chemistry, was lacking in biology at his time. Synthetic biology couldn’t take off, though, without the development of molecular biology in the mid-1900s, starting with Crick and Watson’s discovery of DNA structure (a topic for another time). Then, the development of fast, easy sequencing sparked our current age of genomics, the study of whole genomes, and synthetic biology had all the tools it needed to become a practiced discipline.

This brings us up to recent developments. Just last year, a research group at the J. Craig Venter Institute, headed by Venter himself, succeeded in creating a self-replicating bacterium with a synthetic genome, the first of its kind. The bacterium, JCVI-syn3.0, has only what Venter’s team determined was the minimal genome necessary for life, a feat they accomplished by “mixing and matching” genes of the small bacterium Mycoplasma mycoides to find which ones a bacterium could live without. In future, Venter and his team see the use of similar synthetic bacteria not only to learn about life, but to engineer it for specific purposes, like biofuel production.

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A colony of JCVI-syn3.0

 

The question is: how synthetic is JCVI-syn3.0? Technically, it’s not really a man-made bacterium. Only the genome was man-made, and that was really only adapted from the genome of M. mycoides. The “shell” the genome was inserted into was simply a living bacterium with the genome removed. This is a big step for synthetic biology, but it has a long way to go before it is truly dictionary-definition synthetic.

What do you think? Have you heard of synthetic biology? Did you hear about the production of JCVI-syn3.0? Tell me in the comments!

Yakutian Horses and Pallas’s Cats: Adaptation to Extreme Environments

Good morning, all! It’s the second Saturday of the month, which means it’s time for a science post. This month, with winter approaching, I thought I would turn my attention to a couple of animals that are well adapted to cold environments: the Yakutian horse and the Pallas’s cat.

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The Yakutian horse is a breed of horse that lives in the Yakut region of Siberia; the Pallas’s cat is a species (Otocolobus manul) with a widespread range, from the Caspian Sea to northern India to China and Mongolia. Both these mammals show some common adaptations to cold environments, like small size (Yakutian horses are a bit smaller than most horses, and Pallas’s cats are only the size of a house cat) and long fur. According to the BBC, ancient woolly mammoths had similar adaptations, which enabled them to survive during the ice age.

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A new genomic study (reported by the same BBC article linked to above) has indicated that Yakutian horses evolved from Genghis Khan’s Mongolian horses in less than 800 years, basically the blink of an eye. Since they adapted to the harsh Siberian winters (with temperatures down to -94 degrees Fahrenheit), they’ve been indispensable to the Yakutian people, for food, clothing, and transportation.

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Pallas’s cats, in contrast, are wild. They live mostly in rocky areas at high altitudes (according to ARKive), and indeed, they’ve been found high up in the Himalayas where only snow leopards were thought to roam (see PBS’s “Nature: The Story of Cats”, episode 1). They’re active mostly at dawn and dusk, and hide in rock burrows the rest of the time to avoid predators. They’ve been known to inhabit burrows abandoned by other animals. To help them avoid predation, their fur changes color seasonally for camouflage.

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Here you can see just how fluffy the Pallas’s cat is.

 

That’s it for today! What do you think? Have you ever heard of these animals before? What do you think of them? Do you like winter as much as they do? Tell me in the comments!

Chlorophyll, Carotenoids, and Anthocyanins, Oh My (Why Leaves Fall in the Fall)

Well, it’s October, which means that here in New England, it must be leaf-peeper season. Drive up Interstate 93 anytime around now, and you’ll probably see hordes of license plates from more southerly states on cars packed in to see the leaves in the White Mountains. We residents refer to them fondly as “leaf-peepers” (and sometimes do some leaf-peeping ourselves).

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The White Mountains with fall colors.

 

So what does all this have to do with those three long words in the title of this post? Well, for my science post this week (which I normally do on a second Saturday, but I had a guest post  last week–check it out if you haven’t yet!), I thought it would be seasonally appropriate to talk about the biology behind leaf colors, the defining symbol of fall. And since I’m interested in plant biology, this is also right up my alley.

So during the spring and summer, leaves are green. This is because of Pigment #1 listed in the title: chlorophyll, the major photosynthetic pigment in plants. Chlorophyll is very important for exciting electrons and causing biochemical cascades and so forth, and all of that eventually leads to the plant producing its own glucose, which it can then use in respiration to essentially make energy for cellular mechanisms. So for most of the year, trees are green. Then why does it change in fall?

Well, in the fall, the weather starts getting colder, and the plant starts to go dormant in order to survive the winter. As the U.S. Forest Service explains, leaves are thin and contain a lot of water that could easily freeze in winter, so deciduous trees must get rid of them in order to survive each winter. And as nights get longer in the fall, the plant senses that it’s time to get rid of the chlorophyll, and Pigments #2 and #3, carotenoids and anthocyanins, show their colors, so to speak. Carotenoids, which are always present in leaves, cause yellow and orange colors. Anthocyanins, produced only in response to sugar buildup, cause reds and purples.

What affects leaf color? Well, you may have noticed it depends on the kind of tree. Oaks mainly have brown leaves (which, incidentally, don’t usually fall off until spring), beeches have lighter brown, and maples can be orange or red or other colors depending on the species.

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Maples in fall.

I found it interesting to learn that weather also affects the colors of leaves. Warm, sunny days cause buildups of sugars, and cool nights constrict the plant’s vessels, causing the sugars to stay in the leaves and the subsequent production of anthocyanins. Soil moisture can also affect leaf colors; if there’s a summer drought, for instance, color onset will be delayed a bit. The best colors occurs if there’s a warm, wet spring and good summer weather, according to the Forest Service.

One last question: what causes leaves to actually fall off? Starting early in the fall, xylem and phloem veins (veins that bring water and nutrients to leaves) start to close off, eventually leading the leaf to fall. The tree is left with only its winter-hardy tissue, giving it a better chance of surviving the winter. As an addendum, some trees actually have winter-hardy leaves that only fall due to old age. We know them as the evergreens: pines, spruces, hemlocks, and other trees with needle- or scale-like leaves. The waxy coatings on their leaves make them hardy enough to keep on photosynthesizing all winter long.

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Which is why people use evergreens as Christmas trees: they’re still green.

 Are your leaves turning colors yet? Have you ever thought about why they turn colors in the fall? Are you going to go “leaf-peeping” this fall? Tell me in the comments!

Class Project to Blog Post: A Word on Photosynthesis

Greetings! Once more, it is the second Saturday of the month, and I find myself scrambling to put together a post about science. Fortunately, I’m a genetics student two weeks into her third semester, and need not look too far for interesting topics.

Inspiration comes in various forms. Why shouldn’t it come in the forms of happy little houseplants?

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A jade plant, Crassula ovata.

I’ve kept jade plants for years. They’re a kind of succulent (a water-conserving plant with fleshy stems and leaves, something between a normal plant and a cactus) which, not surprisingly, grows well even when you forget to water it. Plus, every time a branch breaks off, if you stick it in a pot, you get a new plant. (I keep getting more of them that way.) They look cool, make great bonsai projects, and even flower once in a blue moon. And as this is a science post, not a gardening post, I bet you’ve already guessed that jade plants are also scientifically interesting.

All plants use photosynthesis to “fix” carbon dioxide into glucose, which can then be broken down in respiration to get energy. It’s more or less equivalent to making one’s own food. There are different ways of doing this; the most common is C3 photosynthesis, more or less the “normal” pathway. C4 photosynthesis is found most often in tropical plants, and involves some extras added to the C3 pathway to maximize carbon dioxide uptake in environments where the gas’s availability is limited. In both of these pathways, stomata (small openings in plants’ leaves) allow carbon dioxide into the plant.

Crassulacean acid metabolism, or CAM, photosynthesis adds on further to C4. It is found mostly in desert succulents like cacti and jade plants, and in fact was named after the jade plant’s family, Crassulaceae. In CAM photosynthesis, the stomata open only at night, when the temperature is lower and the water within the plant will evaporate less than it would during the day. The plant then takes in carbon dioxide, fixes it to an intermediate molecule, malate, and stores it to be processed during the day. This cool adaptation helps cacti and succulents survive in their desert environment.

One more note: I haven’t said anything about the first part of the title yet. Well, I’m taking genetics this semester, and I need to do an honors project on a gene that interests me. While poking around for genes involved in drought resistance in plants, I rediscovered CAM photosynthesis, which I learned about a few years ago and thought was really cool. There you are; inspiration from a class project. It really does come from various places.

(My source for this post was The Physiology of Flowering Plants: Their Growth and Development, third edition, by H.E. Street and Helgi Opik.)

Isn’t CAM photosynthesis cool? (If you don’t think so, I totally understand. I know lots of people probably don’t get why I’m a plant nerd.) Have you ever had a jade plant, or a cactus or something similar? If so, what was your experience with it? Tell me in the comments!

Are Allergies Genetic? (Said the Science Nerd)

Yes, yes, on second Saturdays of the month, everything I say is from science-nerd mode, isn’t it? Specifically biology-nerd mode. I suppose that’s what happens when one is a genetics student.

Really, though, a couple of things influenced me to ask myself this question. Number one, I am a genetics student; therefore, I am curious about genetics. Number two, I have allergies, as does everyone else in my family. We’ve been sneezing off the hook for about three months now. I am mostly allergic to pollen (a real letdown for a plant lover), but people in my family are allergic to all sorts of things: horses, corn, sheep, hazelnuts, cats, you name it. So I wondered: are allergies genetic?

I asked Google that question, and it was kind enough to direct me to this interesting article, which not only answered my original question, but added more to the answer. It turns out that allergies are genetic, passed from parent to child. They are also sex-related; for example, girls are more predisposed to have allergies if their mothers also have allergies, and vice versa for boys.

Another article points out that there are different kinds of “allergic diseases,” including eczema and asthma as well as hay fever (pollen allergy). And, like anything else, allergies are influenced by environmental factors, including air pollution, chemicals, and types of animals and plants in the area, as well as by genetics. (See this abstract for more.)

Well, this turned out to be a short post. There are some quick facts about allergy genetics for you!

What do you think? Do you have allergies or something similar, like asthma? If so, do your family members have it, too, and have you ever wondered whether it was genetic? Tell me in the comments!

Mosquitoes, Malaria, and Molecular Biology: How DNA can Help Kill a Disease

Happy second Saturday, everyone! It’s time for a science post. For today’s post, I visited the Science News website and browsed around for something interesting to talk about. There were a lot of options, but I settled on this one. All credit goes to the original authors.

I’m sure you’ve heard of malaria. It is commonly known to be rampant in third-world areas, particularly Africa. It’s caused by microorganisms of the genus Plasmodium, which have part of their life cycle in mosquitoes of the genus Anopheles. This makes it that much harder to eradicate, since any disease or parasite with what’s called an “animal vector” requires health workers to eliminate every animal that could carry the disease. Imagine trying to kill every one of the 30-40 malaria-transmitting Anopheles mosquito species in Africa, and you have some idea of why malaria is so hard to get rid of.

So essentially, to end the disease, end the mosquito. But how?

Using everyone’s favorite molecule, of course: DNA!

Scientists at Imperial College London have developed a “gene drive,” an engineered DNA molecule that disrupts genes’ activity by inserting itself into them, that is capable of sterilizing females of one Anopheles species. That could curb the reproduction of the mosquito, and thus the number of mosquitoes available to carry Plasmodium. 

 

 

Plasmodium, the malaria parasite. (Image from the CDC)

This is actually the second Anopheles gene drive to be developed by the same researchers. The other one (findings published 2015) aimed to prevent Anopheles from carrying Plasmodium. So far, both of them work, though neither has yet been released into the wild Anopheles population. But both have potential to help stop malaria.

There you have it: another manifestation of the current genetics revolution. (I must admit I am partial to blogging about said revolution, being a major DNA geek.) What do you think of these gene drives that might help eliminate malaria? Do you like DNA as much as I do? Share in the comments! Also, if you’d like to learn more about today’s topic, be sure to check out the links in the post!

A Blurb on Bioinformatics: Why We Geneticists Need Computers

I was going to write a longer post for this week, but due the three finals I’ve had in the past two days and the one I have coming up on Monday, I found myself scrambling to put a post together. I may tackle the Human Genome Project (today’s intended topic) another time, when it’s not finals week. Today, I will offer one of my favorite scientific rants: bioinformatics.

Or, why geneticists should learn computer programming. (Image not mine)

The above image shows you a schematic (technically called a “space-filling model”) of DNA, deoxyribonucleic acid, one of my favorite molecules and one of the most awesome things in the universe. (But I digress. . . .) Here is a simpler picture of DNA for you.

(Image not mine)

 

 

This image clearly shows the iconic DNA double helix, along with something very important: base pairing. As you may have heard in high school biology class, DNA’s information is encoded in the “base pairs,” pairs of nucleotide bases (adenine, thymine, cytosine, and guanine) that hydrogen-bond with each other. (Don’t worry about what a hydrogen bond is. It doesn’t really matter unless you’re a biochemist. What matters is that the bases pair.) Adenine (A), as you can see in the image, only pairs with thymine (T), and guanine (G) only with cytosine (C). This is responsible for a lot of important properties of DNA, such as coding for proteins and RNAs, which I won’t go into here. This is why knowing the “sequence” of bases along the DNA in a chromosome, or in an entire genome (all the genetic material in an organism), is useful.

Here is an illustration of chromosomes for you. (Image not mine)

The problem with that? Any given organism (even a bacterium!) has a lot of DNA.

Take humans, for example. Almost any given cell in your body (except red blood cells, which have no nuclei) has a copy of your entire genome, coiled up into 46 chromosomes, two copies each of 23 unique chromosomes (except the X and Y chromosomes, which are not copies of each other, per se). All together, those little chromosomes contain about 2 meters (5-6 feet) of DNA. Think about it: if stretched out, your DNA would be about as long as you are tall. That’s in each cell, folks.

It staggers the mind. Which is why we need computers.

This is where we get “bioinformatics”: using computers to study life. (Image not mine)

Genomics (the study of whole genomes) is having a revolution right now. And this field of study relies on computers, so guess what? Bioinformatics is big. Programming classes are offered for bioscience majors, and bioinformatics options for computer science majors. Though I’m not a genomics student, I will probably take a bioinformatics programming course later in my college career, because that’s where the field is going. And there you have it, ladies and gentlemen. My genetics rant for the day. I hope you enjoyed it.

(Image not mine)

Have you ever heard of bioinformatics? Do you like DNA as much as I do? (I know, I know, I’m a nerd. . . .) How about computers? (I don’t like them very much, but it’s great if you do. The world needs more computer people.) Share in the comments!

Ecology of Certain Forest-Dwelling Members of the Bryophyta; Or, Why Mosses are Underrated

 

Plants are everywhere. As my last semester’s biology teacher put it, you don’t look down from space and see the animals running around; all that green you see is from plants. It is plants. Like this:

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A boreal forest in Canada. (Image not mine)

So in this week’s science post, I want to talk about plants, but not those plants in the picture above. Instead, I want to talk about these:

These “plants” are all examples of boreal feather mosses. And I am here today to tell you a bit about their ecology, in order to illustrate why mosses like these beauties are sadly underrated.

In the northern boreal forest (like the Canadian one shown above), these mosses have to compete with various vascular plants (which have internal water- and nutrient-carrying systems, a bit like an animal’s veins and arteries). But the mere fact that mosses have no vascular systems gives them an edge over vascular plants when it comes to photosynthesis (which is how a plant makes its own food). Let me explain.

If you picked a leaf off a vascular plant (like one of the trees shown above) and looked at it under the microscope, you would find a whole bunch of tiny little holes, called stomata. Stomata open and close to allow the plant to absorb the carbon dioxide it needs for photosynthesis without losing much of the water it also needs for photosynthesis.

But mosses have no stomata; their entire bodies can just absorb as much carbon dioxide and water as they need. So a moss that lives in a “sunfleck” on the forest floor, one of those shifting spots of sunlight amidst the shade cast by the trees, can react better when the sun moves and casts light (also needed for photosynthesis) across that spot than a vascular plant, which has to take the effort of opening its stomata, could.

Boreal mosses are also important for succession; this is when something disturbs the ecological community and the members of the community (the different species that live there) must react. When a tree falls down, for example, it disturbs the plant community around it. Mosses and their relatives have been found to move back in sooner than other plants. This is probably because they have more varied reproduction methods than vascular plants; they readily reproduce asexually, which makes them able to colonize new areas quickly. Here, again, they have an advantage over vascular plants.

Mosses can also compete with vascular plants in a more direct way than those described above. In New Zealand, eleven moss species have been found to have allelopathic effects on plants, including native trees. (In allelopathy, one plant secretes chemicals that actually inhibit the growth of another plant.) Specifically, these mosses’ secreted chemicals inhibit the germination and root growth of other plants. This makes them better able to compete in the crowded New Zealand forest.

 

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Dendrohypopterygium filiculiforme, an allelopathic moss species. (Photo not mine)

So, to wrap up this long blog post, mosses are both pretty and interesting. They’ve adapted in ways that allow them to compete with vascular plants, such as speedy photosynthesis and growth-inhibiting chemicals. They’re also important for succession after forest disturbances like treefall. Altogether, these simple plants are interesting, important, and very underappreciated.

Tell me in the comments: What did you think of mosses before? What do you think now? Do you find these snippets of moss biology as interesting as I do? Did you understand everything I said, or did I use too many technical terms?

Also, if you are curious enough to brave a couple peer-reviewed articles today, here are my references!

Jonsson, B.G., and P.-A. Esseen. 1998. Plant colonisation in small forest-floor patches: importance of plant group and disturbance traits. Ecography 21: 518-526.

Kubásek, J., T. Hájek, and J.M. Glime. 2014. Bryophyte photosynthesis in sunflecks: greater relative induction rate than in tracheophytes. Journal of Bryology 36(2): 110-117.

Michel, P., D.J. Burritt, and W.G. Lee. 2011. Bryophytes display allelopathic interactions with tree species in native forest ecosystems. Oikos 120: 1272-1280.