I am excited to announce that my wife and I just completed our move to Canada to start our new post-docs this week! I will be working with Stephanie Doucet at the University of Windsor. I will be continuing to study the evolution of coloration in birds, but in collaboration with Stephanie and her husband, Dan Mennill, I will also be studying the co-evolution of color and song. This is particularly exciting for me as I am interested in studying multiple signals and while hummingbirds and many other birds/animals communicate using elaborate dances and ornate color patches, they also signal in other modalities like acoustic or odor signals. Additionally, I will continue to study the mechanisms of color production in hummingbirds using electron microscopy. I will be looking at the surface and internal structures of hummingbird feathers to understand how these structures co-evolved with their feather reflectance, color appearance during displays, and courtship dances.
In the meantime, my recent publication from my dissertation in Ecology Letters picked up some popular press! I was interviewed by a writer from Science for their news section, and they both wrote an article about my paper and created a really neat video! Be sure to check them out!
Well its finally time! I am defending my Ph.D. this Friday at 2:00 PM (Arizona time). All are welcome to attend my talk, which will be about 1 hour, and is on Arizona State University’s Tempe campus in Life Sciences E-wing 244 (LSE 244).
My talk will cover my four dissertation chapters on the evolution of hummingbird coloration and courtship displays. I will probably write a summary blog of my dissertation later this summer, but if you want to see the presentation in person, please stop by!
Wow, it is amazing how time flies in grad school. It is hard to believe that is has been over four months since the last time I blogged! The main reason for my lack of blogging these past several months has been my work load. I ended up biting off a little more than I could chew, work-wise, this semester, which kept me from dedicating time to blogging. Luckily, I can say with confidence that I now have much more time to dedicate to this blog and it will not just disappear! Plus, I have a lot of exciting prospects in the future to talk about, so there will be no shortage of material to write about!
While most of the work things that kept me from blogging were not to exciting, I still had some very exciting events occur during that time. Firstly, I was awarded the National Science Foundation Doctoral Dissertation Improvement Grant for $20,085!!!!!This was an amazing and huge success that will go a long way towards some exciting new research ventures. I was also awarded a United States Agency for International Research and Innovation Fellowship and an Arizona State University Graduate College Completion Fellowship!! Combined these grants and fellowships are allowing me to expand my research to studying hummingbirds in Peru and conduct electron microscopy on hummingbird feathers (both scanning “SEM” and transmission “TEM” electron microscopy). The electron microscopy work will allow me to quantify the surface and internal structures of hummingbird feathers that are responsible for producing the amazing colors hummingbirds exhibit, while the trip to Peru will allow me to study several new species for my dissertation work, such as the Peruvian sheartail and oasis hummingbird. Below are a few photos of some scanning electron microscopy work I have done so far.
In addition to getting these grants and fellowships, I also gave my first set of public seminars on my hummingbird dissertation research. I first gave an hour long seminar to the Maricopa Audubon Society (link) and then gave another hour long seminar through the Audubon’s Appleton-Whittell Research Ranch’s Potluck and Presentations series (link). Both of these talks were great experiences, and they seemed to be met with enthusiasm from the audience, which was very encouraging.
Outside of grants and talks I did some fieldwork in March on Costa’s and Allen’s hummingbirds, visited the Grand Canyon and Sedona, went on some adventures in Michigan, and visited my undergraduate university (Trinity University). I will try to make a post out of each of these, but here are a few photos from each.
I greatly appreciate everyone’s patients with my lack of posting, but I am very happy to be back and excited to start blogging again! I would also like to give a shout out to my old school friends from Houston – Gabe and Carl. Thank you for keeping up with my blog!!
In the end, things went very well, and the film crew seemed to have gotten all the shots they wanted. But before I get into how everything went, I wanted to give some background on the broad-tailed hummingbirds.
Broad-tailed hummingbirds are part of a subset (~36 species) of all hummingbirds (330+ species) called the bee tribe. The bee hummingbirds are unique because they are widespread across North, Central, and South America, whereas many other hummingbird tribes are only found in Central and South America. They are also typically very small, ranging from 3-4 grams. The bees are also the group I am focusing on for my dissertation. The reason for this is that most of the species in this group have both colorful throat plumage (also called a gorget) and stereotyped courtship display behaviors. Most species have two types of display behaviors: the shuttle and dive displays. The dive display is when a male flies high into the air, sometimes over 100 ft, and then plummets down towards a female, pulling up near her and flying back high into the sky to repeat the behavior. During this dive display, the male opens up his tail, which males a sound. The other display is called the shuttle display, which is the focus of my work. During this display a male hovers back and forth in front of the female with his gorget flared and facing her. Across the species in bee hummingbirds, there is a great diversity of coloration and there is quite a bit of variation in their courtship displays, especially the shuttles:
Costa’s – https://www.youtube.com/watch?v=_bdEma-rnS8
Black-chinned – https://www.youtube.com/watch?v=j_Xf3tnQJqg
Broad-tailed – https://www.youtube.com/watch?v=FWWuhbVF_qM
Like I mentioned above, broad-tailed hummingbirds are part of this tribe, and thus have a colorful gorget and their own versions of the shuttle display (see link above). This species is one of my favorites, partly because they were the first I worked on, but also because they are high elevation specialists, which means I get to do my fieldwork in the mountains! I’ve typically found this species from 5,000 to 7,000 feet, but I know I’ve seen them as high as 9,000 feet. They mostly occur in Arizona, Nevada, and throughout the lower Rocky Mountains (New Mexico, Colorado, Utah, Wyoming), but they also have footholds in several other states like California. I’ve found them in a range of habitats from alpine meadows to piñon-juniper forests to mixed-coniferous forests, like the following pictures.
They are common visitors to feeders at high elevation towns as well. Broad-tailed hummingbird males, like some other species in the tribe, make near continuous trill noises when they fly, created by their wing feathers, which is actually quite pretty to listen to. The sound is quickened and amplified during their shuttles, as you can hear in the video. Here is another video, though not the best quality, of a male shuttling. This video is looking at the male over the female’s shoulder, but it is not focused on the male because he is moving too fast for my camera.
This video is also what the film crew was working to capture, though they have a $50,000 dollar camera that films at 4k, so it will be much much much higher quality. They also filmed the male displaying at an angle without the cage in the view. Luckily, on the last day of filming, we found a very cooperative male who shuttled many times for us and in the right spot, which allowed the film crew to get all the shots they wanted.
Overall, it was a great experience to work with this crew, and I learned a lot about the process to make a nature documentary from start to finish. I really hope to work with the Coneflower Studios again, and I will let everyone know when the documentary will be shown on PBS and out on DVD! Below are some pictures of the crew in action. Coneflower studios producer Ann Prum manned the camera, while associate producer Melanie Quinn was recording audio and helping me with the cage set up. The little camera to the side is mine.
This past Tuesday I passed my comprehensive exam! It was a huge relief! Also, this is why I haven’t been blogging as frequently lately.
To explain: at ASU for my Ph.D. program, we have to take a roughly three hour oral exam given by our dissertation committee. This exam not only tests our knowledge in our fields of study, but also is when we defend our dissertation proposal (all of our ideas/hypotheses/methods/data to date). My committee is comprised of my advisor and 4 other faculty, who are experts at various topics covered in my dissertation. For instance, I have an expert on phylogenetics, an expert on hummingbirds, an expert on iridescent coloration, and an expert on statistics. During this exam, they can ask me questions on anything related to my proposed dissertation, even if I’m not directly studying that topic. For example, I was asked questions ranging from how to build a phylogeny to the genetics of behavior.
To prepare for this exam, I have spent the past month doing nothing but studying, everyday, all-day. And before that I spent most of my free time during field work writing/editing my proposal. This is definitely one of those exams that you have to study more than just a few days before! Above is a picture of some of the material I read; I have a library of papers on my computer which I also went through.
While the entire process was fairly miserable, I did learn a ton. Not everything I read came up during my exam, but I am ok with that because that knowledge will still serve me through the rest of my academic career. This also seems to be part of the point of this exam. It forces you to study and learn a bunch of material, that will ultimately make you a better scientist.
Now that this exam is over, I can breathe free again and relax! I will post the final updates on the documentary filming in a few days, and then I will probably post my tips and advice on studying for this type of exam to hopefully help those who will take it in the future.
Thank you so much to everyone who supported me throughout this entire processes!
Things have been going very well so far. First off, we are in such a beautiful area – the Santa Catalina Mountains, near Tucson, AZ. These mountains are part of the sky islands (mentioned in a previous post) that are located throughout south-eastern Arizona. Essentially, the sky islands are a series of isolated mountain ranges that are surrounded by desert or grassland. This is one of the more northern chains, and is a smaller range than others. Due to its proximity to Tucson, it is one of the more popular ones, and Mt. Lemmon, the highest point in the range, is very famous. There is even a ski resort and tiny town called Summerhaven contained within these mountains. The Santa Catalina mountains are full of trails and campsites, which made things logistically much easier for us to find good filming locations.
The film crew has found several nests that they are watching and getting some excellent shots. These females are apparently super tolerant and allowing the cameras to get very close to them. I’ve been able to get some good pictures of females on their nests and some rare shots of fledglings and feeding behaviors. Hummingbirds make their nests out of lichen and spider webs. The spider webs not only help hold the nest together, but it also makes the nests flexible and spongy so that as the chicks grow, the nest can expand. Though, by the time the chicks are about the fledge, the nest is so full that mom can’t really sit on it anymore. These nests are also usually very hard to find, not only because they are small, but because they are well concealed within a plant.
Most hummingbirds seem to lay two eggs, that are very tiny to us, but actually quite large compared to the female. Females will incubate the eggs for 2-3 weeks, and then will feed the fledglings mostly insects. Nectar doesn’t contain the necessary proteins for development, which is why females will switch to a more insect heavy while feeding young. Hummingbirds always incorporate insects into their diet though, as this is their source of essential proteins. Males do not help with nesting or raising young at all. Depending on the length of the breeding season, females can have multiple clutches, as several of the females did at our site. Also, an interesting fact: because hummingbird legs are so small and not good for walking, when a female is perched at the edge of her nest, she can’t really hop into it; instead she has to hover into it. Here are a few pictures illustrating the nesting and raising of young in hummingbirds.
I’ve been focusing on finding male territories and trapping females so that we can elicit and film some male courtship displays. The place we are filming is quite full of broad-tailed hummingbirds. I’ve also seen several other species here including broad-billed, black-chinned, and magnificent hummingbirds. I’m pretty sure I heard an Anna’s hummingbird at one point too. We are up about 8,000 feet, which is typically too high for Anna’s.
At this point, I’ve found several male territories, all throughout the area, and identified several males that would be good to film, such as this one:
I’ve also set up feeders so that I can trap some females and use them to get males displaying. Sometimes setting up feeders has the added bonus of creating new male territories, as males will come and claim feeders for their own. It is unclear whether males of this species select territories based on resources or form what are called leks – a spot with a single or multiple males, where females go to mate, but receive no other resources, typically. Based on my observations with this species, I would say they lek, as most males do not have any flowers on their territories and have to leave their territories to feed. However, males will guard valuable resources like feeders, as these are permanent and consistent sources of food. Overtime as the feeders attract more and more hummingbirds, these males will actually end up spending most of their time chasing away rivals, which might interrupt their ability to court females.
In my next post, I’ll have details on how the filming went and hopefully have some videos of my own to show. For now, I’ll end with a surprise I met while scouting for territories. I nearly stepped on it, and it gave me quite a fight!
In some very exciting news, I will be helping a nature documentary crew film hummingbird displays for PBS Nature!
It started several months ago when Ann Prum, producer of Coneflower Studios, contacted me about filming broad-tailed hummingbird displays. She wanted to film the whole life history of broad-tailed hummingbirds from courtship to nesting to fledging, and I was to help elicit male dive and shuttle displays. Ann had previously worked with my Ph.D. committee member and hummingbird expert Dr. Chris Clark, who passed my name onto her. Chris has not worked as much with broad-tailed hummingbirds as I had, and I have a good field site to film them. So we made the arrangements to start filming this summer. I’m super excited for this opportunity to help with with this award winning documentary team!
Coneflower Studios has already produced an amazing documentary on hummingbirds called Magic in the Air, which I highly recommend. More recently, they produced another great documentary on ducks (An Original Duckumentary), which won an Emmy, and a three part series called Animal Homes. Something that I really like about this studio, is that they not only film some amazing natural history, but they contact and feature scientists in their films. While I am not going to be featured myself, there will be several people that I know in this new documentary.
I just recently had my first first-author paper accepted for publication in Proceedings of the Royal Society of London Series B! The paper was the result of work I started as an undergrad at Trinity University, where I worked with both Troy Murphy (link) and Michele Johnson (link) on my honors thesis. It is crazy to think that I started this work four years ago. Briefly, we were testing a novel hypothesis to explain the geographic patterns of sexual differences in coloration in wood-warblers. The geographic pattern is that as you move north away from the equator, birds (not just wood-warblers) seem to exhibit greater differences in coloration between the sexes (sexual dichromatism). We hypothesized that this pattern was driven by evolutionary increases in the distance species migrated. We thought that longer migration distances would be costly to individuals, which would select against being colorful, which is also costly. However, males gain great benefits by being colorful since they use their coloration to attract mates (females do not do this), so we predicted that males would maintain their coloration while females would lose it – thus the observed geographic pattern. Through our work, we found that this hypothesis was indeed supported! Check out the paper here. Excitingly, this paper has been picked up by several science news outlets, such as Science, Nature, and IFL Science. Be sure to check them out as well!