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Species, Part One

February 25, 2017

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Darwin’s Finches, courtesy of Welcome Images

In the next few posts we’ll be discussing the concept of species and why that’s important to urban biodiversity conservation. I think a common conception of conservation work is that it’s all about protecting species, but that isn’t quite right. Conservation projects actually target three levels of diversity: species, yes, but also genetic and ecosystem diversity. However, being humans, we’re attracted to things we can relate to, and most of us can relate better to organisms than to genes (and even more so to individuals), and perhaps this is why there is so much focus on species.

Many people remember the definition of a species that they learned in high school biology: members of a species can interbreed with each other and produce viable (i.e., alive and non-sterile) offspring. This is what’s commonly termed the biological definition of a species. But the concept of a species is actually quite slippery – and that’s not even going into the differences between a species and a subspecies (deciding whether two populations are different enough from each other to belong to different species, or just different enough to belong to separate subspecies of the same species, can be quite the debate).

Canids provide a good example of why the biological definition of a species can be problematic. No one would argue that a wolf is not a dog, which is not a coyote, but all three can interbreed and produce viable offspring.

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Thomas Brown, 1829. In the Public Domain.

So, how else might we go about defining the concept? Traditionally, the morphology of animals was considered, with like grouped with like. This was done by looking at the color of specimens, taking measurements of various body parts (skulls, other bones, wingspan, and so on), body parts, and other physical components of organisms that can be measured and quantified. Statistical tests were then done to look at how these measurements could be best grouped together. If a bunch of specimens best group together into two groups and not only one, the theory goes, then you’re looking at two separate species.

These days we can also look at this from the molecular level, through genetic analysis of a specimen (or, rather, of a very small piece of a specimen – hair and scat can be used for non-invasive testing). In some ways this is similar to looking at the morphology of a specimen – you’re basically counting genes and seeing how many differences there are between one specimen and the other. That’s of course an over-simplification of both the process and the analysis, but for the purposes of our discussion, we’ll leave it at that.

On a tangent, I highly recommend a book that came out last year, The Dragon Behind the Glass: A True Story of Power, Obsession, and the World’s Most Coveted Fish, by Emily Voigt. The book isn’t entirely relevant to the urban wildlife world (and yet is entirely relevant in some ways), but it does a great job of discussing the slipperiness of the species concept and the benefits and drawbacks of using a molecular definition.

More on species to come!

First Winter Weather!

December 17, 2016

Our first wintery-weather hit us last night. Not much — just a bit of ice — but enough to make us want to stay at home with some hot chocolate! It’s already starting to warm up, so the ice is not long for this world. 

Nature Helping Us Heal

December 1, 2016

Last week we had an unanticipated trip to the ER. While we were waiting for the doctor they pulled a curtain around us, and lo and behold it was covered in botanical prints! My husband pointed out that this might make for a good blog post, and it is a good example of using nature (or in this case representations of nature) in an effort to provide comfort in some way.

There was a landmark study in the 1980’s by Roger S. Ulrich that looked at recovery times for surgical patients. One group had rooms with views of trees and the other views of a brick wall.  Turns out the patients with the views of trees statistically had shorter hospital stays, and took fewer doses of narcotics for pain management, among other measurements of surgical recovery. So it makes sense that incorporating nature, or even representations of nature, in medical settings can be beneficial to all.

Ulrich, R.S. 1984 View through a window may influence recovery from surgery. Science 224: 420.

Letter to Students re: Election

November 14, 2016

This is what I sent my master’s students a couple of days after the election. I thought long and hard about what to say, and read a few other letters to students for some inspiration (including this great one from Josh Drew’s lab at Columbia University). I did think it was important to say something, though, since no matter who they voted for, given that they are in a masters of natural resource management program, my assumption is that environmental policy is meaningful to them. Given what the next administration is likely to do on that front, I think it’s time to roll up our sleeves and get to work no matter what other political beliefs you hold.

The only thing I wish I had added was a note that everyone is is always welcome in my classroom, virtual or otherwise. Because that’s the truth.

I’ve thought long and hard about what to say to you about this week, and, in fact, whether or not to say anything. However, this is a course on the conservation of biodiversity, and (most of you) are in a natural resource management program. And a large part of that, whether or not it’s something you want to work on directly, is environmental policy.

No matter who you voted for on Tuesday, or why, it’s clear that in the coming months and years we’ll be facing enormous challenges in our field, both nationally and internationally. I know that you are all up for the challenge, and that you will do great work, on whatever scale and scope you are able and willing to.

The work we do is important, perhaps more so now than ever. Our climate is changing; we are losing vital natural resources; our natural world is becoming impoverished in many ways; people who have less influence and who are disadvantaged both locally and globally have less ability to both combat these issues and survive them; and we are facing an anti-science crisis in this country, where many not only do not believe scientists, but think that we are purposefully attempting to mislead the public.

These are challenges we all must face, no matter our own personal circumstances. We might think that we’ll be insulated from the effects of climate change, or the loss of species in far-away parts of the world, for example, but in fact it is our job as people with the resources to make a difference to exercise that ability. I’ve had some energizing conversations with colleagues since the election, and I believe that there will be an ever-increasing number of ways to create change, so there will be something for everyone.

No matter your political beliefs, as members of this academic community I assume that these issues are of importance to you. I think it’s easy for some of us to despair when we think about what lies ahead, while others of us may look to the future with optimism. But I urge you all to dig deep and find it in yourself to rise to the challenges ahead. After getting to know you all during our discussions this semester, I know you can. I’m proud to be your professor.


July 15, 2016

Fowler’s toad, Anaxyrus fowlerii. By Jimpanz, courtesy of Wikimedia Commons.

On Monday evening I joined a group led by the DC Department of Energy and the Environment (DOEE) to go out and listen to frog calls. DOEE started a DC chapter of the national FrogWatch group, a citizen science organization. The goal of FrogWatch is to monitor frog populations throughout the country, relying on trained volunteers. Volunteers go out to their chosen sites (wetlands of some sort or another) after dark, and follow a protocol (stand quietly for two minutes so the frogs adjust to your presence, and then listen for three minutes). They’re not looking to spot frogs, but rather to hear their calls. Frog species all have different songs, used during breeding season to attract mates. Some are melodic (the gray tree frog has a musical trill), and some not so much (the American bull frog sort of sounds like a low-flying propeller airplane). And since different frogs have different breeding seasons, the chorus changes from month to month. Spring peepers are often the first ones out, in February, and late season breeders such as the green tree frog can go until July or August.

To prepare for this, earlier this year I went to a FrogWatch training led by DDOE’s Rachel Gauza, who is based at the Aquatic Resources Education Center in Anacostia Park. The training was excellent — and fun! She got the class into it, especially when she had us mimicking a frog chorus. Our local NPR affiliate even covered the training and the first group outing in a great story — it’s worth checking out.  

Back to Monday, I met the group at the bridge gate to Kingman Island a few minutes after sunset. Kingman Island is an amazing spot — it’s manmade from material dredged from the Anacostia River, and is currently owned by the DC Government and managed by Living Classrooms. It’s truly a bit of wild in the city — you can see the lights from RFK Stadium, and hear and see the rumble of the Metro on a regular basis.

We wandered along the path, heading towards three sites that have already been monitored this year. At the first, we could hear a frog call in the distance, but not at that site. So we moved on. At the next, we were closer to the critters-in-question, so were able to record them. I incorrectly thought we were hearing an Eastern spadefoot (I’d memorized that their call was sort of like a whining old man), but it was actually a Fowler’s toad (they also sound a bit like whining old men!). There’s a great website, DC Frog Calls, which has audio clips of some of the frogs that live in DC if your interested.

At the final site, we heard a green frog. They’re often said to make “plucking” sounds, like a banjo, which I do hear. But I also always think of some impersonations of Mick Jagger, pursing his lips and going “Oo – oo – oo.” I might be alone in thinking that.

It was a fairly quiet night, but was also getting towards the end of the season (especially since it seems like it’s been an early summer — our fireflys came out early, as did our cicadas), and it hadn’t rained in several days. So I was happy that we heard anyone, and I’m looking forward to “adopting” my own patch of wetlands somewhere and doing regular monitoring.

Just to make a pitch for citizen science, it’s always a great way to get to know your local natural world a bit better. Besides learning new skills (some of which are quite complex, and some of which are very simple), it forces you to just stop and really look at something for a while. And it helps research projects that are working on protecting the wildlife around us. Not a bad way to spend an evening.

Green Frog

Green Frog (Lithobates clamitans). By Contrabaroness, under a CC license via Wikimedia Commons




52 Weeks of Urban Nature, Week 20: California Edition

June 3, 2016
52 Weeks Week 20 twitter

(c) Megan Draheim, 2016

We were in sunny San Diego for a conference earlier this spring. Well, it was sunny until our day off from the conference, when it rained the entire day! We still had a good, albeit slightly soggy, time.

I am addicted to palm trees, of all shapes and sizes (I’d probably fit in well with the members of the International Palm Society. Check out this article from the fabulous Atlas Obscura about the Society and their field trips). And yes, I know they’re not native to many of the places they’re grown. But that doesn’t make them any less magnificent! I might have to do a separate post sometime with nothing but palm pictures. But not until after I catch up on posting my 52 week photos.

52 Weeks of Urban Nature Week 19: Unfurling Edition

June 3, 2016
52 Weeks Week 19 twitter

(c) Megan Draheim, 2016

Yes, these are fiddleheads. And yes, my ferns have unfurled themselves into all of their glory already! Needless to say, I have been not so good at posting these in a timely fashion. But I’m determined to get caught up in the next couple of weeks. And I have been faithfully taking a photo a week!

I love ferns — always have. There’s something so beautiful and graceful about them, and at the same time, so, well, prehistoric. We only have a couple, but they’re some of my favorite plants in our yard. And every year I’m fascinated by the way they grow.

Backyard Musings

April 21, 2016
(c) Megan Draheim, 2016

(c) Megan Draheim, 2016

Spring has really, fully sprung! Our spring flowers are in full bloom, our trees are leafing out (or, in the case of our dogwood above, flowering), the weather is warming up, and suddenly everything is just alive again.

I’ve been working near our back door a lot lately, and so am getting the chance to notice all of the action going on in our yard. The cardinal couple that’s taken up residence have been quite busy lately; both have been seen flying around the yard on a daily basis. Our chipmunks have also been seen scampering across our patio (this especially mesmerizes one of our dogs, who sometimes watches closely from behind the door!). Some species of bees are once again buzzing around some of our early blooming plants (we have flowers throughout the season for them). And I saw our resident melanistic squirrel being chased by a “regular” grey squirrel the other week. The newcomer meant business, and went tearing after our black squirrel — up and down trees, over the fence into our neighbors yard, and up their dogwood, where the chaser promptly jumped at the chasee, causing them both to fall quite a ways to the ground. There was a pause in action, and then they were at it again. I was worried that our black squirrel might get chased off (grey squirrels are territorial), but the next day and the next he was back, so all appears to be well. Black squirrels tend to be uncommon in the mid- and southern-part of the East Coast (much more common in New England and Canada), but they’re relatively common in DC, for reasons that I’ll share soon!

All of this reminds me that we’re only sharing the land with our non-human neighbors. So slow down and take a minute to notice the spring activities of your neighbors, and perhaps give them a thought as you’re choosing what to plant in your garden this year (natives!), and how you’re going to plant it (organic!).

52 Weeks of Urban Nature Week 18: Shapes Edition

April 17, 2016
Washington, DC, (c) Megan Draheim, 2016

Washington, DC, (c) Megan Draheim, 2016

I’ve mentioned before how much I love tree bark, right? This caught my eye on a walk with the dogs — gorgeous graphic shapes, I thought.

52 Weeks of Urban Nature Week 17: Reflections Edition

April 9, 2016


Louisville, KY, (c) Megan Draheim 2016

Louisville, KY, (c) Megan Draheim 2016

Still playing catch-up!

I was in Louisville a few weeks ago and found this image, walking along the waterfront. The waterfront there has always puzzled me a bit — it’s a grand riverfront with what could be a great path walkway, but it’s almost all paved. In fact, this little bit of green is pretty much the only green I saw! I hope there are plans in the future to turn this into a much more useable, pleasant space — one that will help the residents of Louisville get to know their river a bit better.

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