Gimme Your Lunch Money!: Feeding Behaviors in Hummingbirds

Ubatuba, São Paulo, Brazil; 9 October 2014 © Almir Cândido de Almeida

I just put out my hummingbird feeder this season. It didn’t take those little guys long to find it either. Now I’ve got their cute little bodies whizzing about all over the place. They need Yackety Sax to play as their soundtrack. But it got me to thinking about hummingbirds and to looking through recent papers for a good study. I came across one in Zoologia about the feeding behavior of hummingbirds in artificial food patches. Perfect.

First, a little background on hummingbirds. They belong to the family Trochilidae and are closely related to swifts. Males are typically more colorful that females, having highly reflective feathers on their chest and heads. Perhaps these birds are best known for their unique flying. They are able to produce power with both the down- and up-beat of their wing flap, getting 75 percent of their lift from their wings’ downstroke and the remaining 25 percent from the upstroke. This allows for both increased agility and sustained hovering ability. They are the only birds that truly hover and fly backwards. They also move those wings really fast: 60 times per second! So it is little wonder that they have among the highest metabolic rate among vertebrate animals.

Hummingbirds are specialized and consume predominately nectar. To collect enough nectar to maintain that high metabolism, they forage many flowers each day. But not all flowers are created equally. Their sugar concentration can vary between 20-25 percent. In order to get the most sugar-bang for their hover-buck, hummingbirds must select and protect the richest food patches in their area. Three behavioral strategies have been observed for foraging:

1) Dominance/territoriality – a bird will defend its flowers
2) Intruder/subordinance – a bird sneaks into other patches until it is kicked out
3) Trapline foraging – repeatedly visiting a set of plants in different patches without being territorial.

Often, a bird will perch near a good food source and let others know that it is theirs. But defending a territory can be up to three times more energetically expensive, so those flowers need to be really good.

The researchers conducted their study in Itacolomi State Park in the city of Ouro Preto, Minas Gerais, southwestern Brazil, in the Atlantic forest remnant. They created four artificial food patches, each patch containing a single sugar-water solution concentration of 5, 15, 25, or 35 percent. They observed the birds (using binoculars) for 3 hour stretches in the early mornings and late afternoon, recording all behaviors during that time. They looked at the time spent in each food patch and the behaviors of the birds (feeding, alert, vocalizing, expelling, fighting, frightening, expel attempt) in each patch. In this way, they could identify the birds’ strategies.

They found that the most-visited feeders were those containing the highest concentration of sugar. Five of the seven species observed fed more on the 25-35 percent sucrose feeders. But there was a difference in the frequency of visitations for different species. The Brazilian ruby (Clytolaema rubricauda, pictured above), Scale-throated hermit (Phaethornis eurynome), and Phaethornis spp. visited the 35 percent feeder more often. And the Brazilian ruby won most of the aggressive encounters with other hummingbirds, both total and in individual patches. This species often stood alert and fought more often, and even “stood impassive” when faced down by the Violet-capped woodnymph (Thalurania glaucopis). I wonder if they looked down their long little beaks at the other birds with a f*ck off attitude? What a badass...hmm, or a bully. The Violet-capped woodnymph visited the 25 percent patch more often, the White-throated hummingbird (Leucochloris albicollis) and Versicoloured emerald (Amazilia versicolor) visited the 15 percent patch more often, and the Glittering-bellied emerald (Chlorostilbon lucidus) was the one that less frequently visited the food patches. Interestingly, the Phaetornithinae applied a hide-and-wait strategy, where they would be chased away by the territorial bird only to hide in the shrubs, remain quiet, and return to the feeder after the dominant bird left the area. Sneaky sneaky. The time spent feeding was found to be correlated with aggressive behaviors and also with body size. Big birds, big appetites, big aggression. The subordinate species chose resources depending on the presence or absence of the dominant species, preferring patches that were not guarded. This may be why they were seen in lower concentration sugar patches more often.

Those itty bitty birds can pack some serious aggression. I guess it isn’t really surprising after seeing all of the chasing that goes on around my feeder. Yackety Sax remains appropriate.

Lanna, L., de Azevedo, C., Claudino, R., Oliveira, R., & Antonini, Y. (2017). Feeding behavior by hummingbirds (Aves: Trochilidae) in artificial food patches in an Atlantic Forest remnant in southeastern Brazil Zoologia, 34, 1-9 DOI: 10.3897/zoologia.34.e13228


If you would like to put out your own hummingbird feeder, I recommend this kind because it is simple, inexpensive and does a great job.

The important part is the big red flowers with yellow centers. Hummingbirds really hone in on those color ques. Do NOT use honey in your feeder! And forget the red dye, if your feeder has red color on it then that is plenty to attract the hummingbirds.

Here is a nice and simple recipe to make your own hummingbird food:

¼ cup granulated sugar
2 cups water

Mix the ingredients in a small saucepan. Bring to a boil. Boil for a few minutes or until all of the sugar is dissolved. Let cool to room temperature. Whatever doesn’t fit in the feeder can be stored in the refrigerator.

Increase the recipe as needed, it's a 1:4 ratio of sugar:water

Change the solution in the feeder every 3 days, sooner if it is really hot outside. Make sure to rinse the feeder each time it is refilled. Scrub away any growths (fungi, etc.) as needed.


Brazilian Ruby picture via The Cornell Lab of Ornithology
Feeder image via World of Hummingbirds

The Mockingbird Problem

In the past, I've had this exact problem with a mockingbird. Currently, I'm having a problem with a Carolina wren that isn't aware that it isn't supposed to be singing outside my bedroom window at 3 a.m.

(via Bird and Moon)

The Paper Bird Projects

Diana Beltran Herrera is an artist that is inspired about everything that exists in nature, animals, humans, everything that has a life, a shape, a color. She questions "what is the life, where is the point where it starts...everything that exist in the space, and then, discover that in this relations, things are created, transformed, improved in this constant evolution." For her, the movement is the big question and she wishes it understand it in a way that it can be communicated to others and allows people to relate to one another.

These first three pictures belong to her project Salida de campo (Field Trip) where she collaborates with Colombian photographer Victoria Holguín to put the art "subject" into a real context that provides information about its relationship to the environment.

These next three pictures are from her Colibri investigations project where she explores hummingbirds and their relationships to plants.

These final three pictures are from her Studies of movement project where she analyzes the movement of birds in relation to space.

If you like these then go over to Diana Beltran Herrera's website to see lots more!

One-Third for the Birds

For this post I was looking for something a little different. Not so much a weird topic, but more like a topic that I haven't really posted on before. I came across an interesting article about predator-prey relationships as they relate to population sizes. It is one of those basic dynamics that is taught in almost every biology and/or ecology class there is, and rightfully so, because when you get down into it it is actually pretty interesting, no to mention really important.

Most people think they know predator-prey relationships. One thing eats another thing. The organism doing the eating is the predator and the one that is eaten the prey. That is perfectly true. Now think about it in terms of evolution. The predator and the prey evolve together, what is usually referred to as the "evolutionary arms race." If the predator does not catch any food then it does not survive; those that evolve better ways to catch food survive (speed, stealth, smell, sight, etc.). If the prey gets caught by the predator then it (obviously) does not survive, and so it evolves better ways to evade predators (camouflage, speed, poison, etc.). It is important to point out that both the predator and they prey are both adapting, a type of co-evolution. Next, think about the system in terms of population. The interaction of predators and prey greatly affect their population sizes, often on several levels within the food chain/web (or tropic pathway/cascade). When predators eat prey they: (1) decrease the population size of the prey, (2) survive, thereby not decreasing their own population, and (3) are healthy, and alive, enough to breed additional predators, increasing their population. So when there are lots of predators you see a big dip in the size of the prey population. You will can make the same types of conclusions when you take the point of view of the prey. When prey is eaten by the predator: (1) they are removed from the population, decreasing population size, (2) are no longer healthy and alive to reproduce, (3) release their food source (if there is one) to increase their population, and (4) by decreasing their population there is that much less food for their predators. These interactions can result in very predictable, natural boom and bust cycles within these populations and is more the focus of today's topic. If you want pictures and graphs then check out the classic lynx-hare relationship and the Lotka-Volterra Model.

A new paper published in Science takes a look at the role of top predators in marine ecosystems. These upper tropic level (UTL) species include seabirds, marine mammals, and large predatory fish. All groups that have been depleted due to human activities. Fisheries impacts cause direct mortality in the targeted species and indirect, often more subtle, mortality lower down in the food chain/web. Fisheries that specifically target lower tropic level (LTL) species (small fish, squid, crustaceans, etc.) threaten those higher tropic level species by directly removing their food sources. However, it can be very challenging to assess the impacts of fishing on food webs, an ecosystem level approach. Think about it: all those predator-prey interactions in the ocean. That's tough. Often what you see is studies, even large ones, taking on a big chunk of the system, modeling how it works based on gathered data, and drawing conclusions or feeding it into an even bigger model. This study in Science specifically looks at seabirds.

Figure 1: A map of the distribution of
seabird and prey species. (click for
larger view)

Seabirds are a good system because they are conspicuous members of the marine ecosystem globally, have been studied and measured for decades, can reflect change at several scales, long-term breeding datasets from several species in several environments exist, and data from systems where prey availability has been measured suggests that seabirds can be used as indicators for forage fish population fluctuations. This study looked at the response between seabird breeding success and forage fish abundance across various species and ecosystems. The modellers compiled 438 data points spanning 15 to 47 colony-years per breeding site, in a total of seven marine ecosystems spanning 19 time series, 14 seabird species and their prey. They crunched a whole lot of numbers, using statistical methods that I'm not going to mention here, to quantify the fluctuations in food abundance and breeding success.

They found something that you usually don't see when you crunch that much data - all their species showed the same response. The results showed that the number of fledglings per breeding pair started to decline and was more variable when their forage fish food source dropped below one third of its maximum observed amount. The prey becomes scarce and as a result the hunting becomes more inefficient. The birds do not have enough food to successfully raise that many young.

Sure, there are the normal high and low cycles that I mentioned at the beginning, and those are natural. However, adding high rates of fishing from humans into it and, as with many other systems, we exacerbate the problem or collapse the system completely. The fish populations never recover from low seabird numbers because predation and habitat destruction by humans still puts a large amount of pressure on the fish, causing chronic food scarcity for the birds. And, as this study shows, this scarcity can have long-term affects on breeding success, can reduce survival in adult birds, and may affect the trajectory of their populations. The thresholds revealed by this study should inform management objectives in balancing predator-prey interactions, a "keep one-third for the birds" approach. If done well, these management decisions can sustain healthy UTL predator populations, maintain LTL fish populations, and could be applied to other marine ecosystems.

Read the paper here:
Philippe M. Cury, et al. (2011) Global seabird response to forage fish depletion -- One-third for the birds. Science: 334(6063), 1703-1706. (DOI: 10.1126/science.1212928)

And a write-up in ScienceNOW called "A Surprising Threshold for Seabird Survival"

Learn more about predator-prey interactions at
University of Michigan's Introduction to Global Change Curriculum's "Trophic Links: Predation and Parasitism"
New England Complex Systems Institute (NECSI)'s Predator-Prey Relationships page
University of Wisconsin-Madison's SSCC page on Predator-Prey Models (Warning: Contains potentially scary math)
A neat demo from Wolfram of a Predator-Prey Model of foxes and rabbits

Also, revisit my post called "To Eat or Not to Eat, That is the Fishy Question" to learn more about how to purchase seafood from green stores or restaurants and guides on choosing the correct seafood.

(image from readysetwhoa.wordpress.com)

Following Birds Following Ants

What is mental time travel? Sounds a little like something from Star Trek or Dr. Who. Actually its pretty simple, its really just a type of memory. It can be broken down in to 2 elements: the ability to remember past events (episodic memory) and the ability to anticipate and plan for future ones (future thinking). One of the reasons it sounds so simple is that, as humans, it is something that we can do. There is some evidence that a number of animals such as corvids, chickadees, rats, and great apes can remember past events in terms of what happened when and where, and there is some evidence that corvids and primates engage in future planning. However, the issue is whether animals engage in mental time travel.

A new ideas paper in Behavioral Ecology reviews mental time travel by looking at bivouac-checking, a specialized behavior of birds that interact with army ants. Army ants (Eciton burchellii) have regular alternating periods of high (nomadic) and low (statary) raiding activity. The statary period often lasts for several days, but when the ants enter the nomadic phase they raid the forest many days in a row. Several species of birds will follow the ants back to their temporary nest (called a bivouac) to inspect its location and assess this activity. This checking occurs in the evening and then the birds return the next morning to check the bivouac before feeding at the ants' raid. Now this raid is the important part. The army ants swarm across the forest floor and flush out leaf-litter dwelling arthropods. This flushing allows the birds to forage the fleeing arthropods. So you can see why it would be beneficial that the birds know when these raids will happen by checking up on the ants, and it is even more benefical to keep track of multiple bivouacs. And this is where the mental time travel comes in to play.

Bivouac-checking behavior may require episodic-like memory. The birds must remember the location of the bivouac so that they can return to it the next morning while also remembering which nests are in the nomadic phase. They must also get there before the ants start their raid. Element 2 of mental time travel is future thinking. That's a tough one. I mean, how do you test whether a bird is making plans for the future? The birds do exhibit some behavior that may indicate future thinking. They check bivouac when they are sated. A bird with a full tummy doesn't immediately benefit by checking a bivouac. There is, however, a delayed benefit when the bird returns the next morning to find the ants raiding again. This dissociation of current state and future need suggests anticipation of future events.

Being an ideas paper this isn't an actual study. The authors are really just suggesting a good model system for the study of mental time travel by describing the merits of the system and providing some interesting questions for a future study.

Read the paper here:
Logan, Corina J., Sean O'Donnell, and Nicola S. Clayton (2011) A case of mental time travel in ant-following birds? Behavioral Ecology: 22(6), 1156-1165. (DOI: 10.1093/beheco/arr104)

Citizen Science. Get Involved.

Citizen science is becoming more and more popular these days. And why shouldn't it? It is an opportunity for volunteers, who may or may not have specific scientific training, to contribute to ongoing scientific research. The volunteer gets the benefit of participating in a task they are interested in and the scientist gets the benefit of many people going through very large amounts of data, allowing them to accomplish their research objectives. It is just a great way to involve the individual as well as promoting public engagement in science.

Citizen science is not a new concept, it has been around for centuries. However, with advances in technology and the rise of the Internet it has become so much easier to get people involved, especially across large geographic areas. And in most cases the human brain is much better at analyzing images and other data than a computer. Add to that the number of replications you can have when multiple people classify the same image and you can see how errors can be decreased and new discoveries made.

So how does this whole thing work and how can you get involved? Well, first, think about a scientific topic that interests you: ornithology, astronomy, climate change, geology...whatever. The scope of science is so big that there is likely a project that fits your interests. Next, you need to find a project. They come in several varieties. First there is the scope: international, national, regional, or local. Next there is the type of activity you want to do: field work, image or data analysis, or just contributing some of your computer's power. And finally, how long do you want to spend working on this: years, months, or hours. That sounds like a lot but once you have figured these parameters out it will make it much easier to find a projects that suits you. Once you have found a project there is typically a short training session to get you familiar with the user interface and how the data should be analyzed/recorded. Then you are all set to do some science!

I've divided some of the most popular citizen science projects down by category, giving a short description of each. Each icon is linked to take you to the project described. At the end I've linked to a couple of general, easily searchable websites that will help you find the project you want.

ASTRONOMY

This is one of the most popular citizen science fields, and the projects that make up the Zooniverse are the most popular of these projects. There are several projects within the Zooniverse to choose from including:

• Ice Hunters
•  Help find the final target of NASA's New Horizons Mission! After passing Pluto (and pending NASA approval of an extended mission, of course) the spacecraft will retarget itself for an encounter with a Kuiper Belt Object (KBO). The target won't be selected until shortly before the Pluto encounter and there will be lots of images to go through to find out where to go next. This is where you come in. Look at pictures of never seen before objects to find out which one we should visit.
• Moon Zoo
• Explore the surface of the Moon! Look through images taken by NASA's Lunar Reconnaissance Orbiter and answer questions about what you see. Identify craters, boulders (called "Boulder Wars," LOL), or any interesting or weird features you come across.
• Galaxy Zoo: Hubble
•  There are hundreds of thousands of galaxies drawn from NASA's Hubble Space Telescope archive. In this project you get to look at the gorgeous imagery from this telescope and classify the galaxies. Are they elliptical, spiral, irregular? Or is there some new type out there waiting to be discovered?
• Galaxy Zoo: Supernovae
•  This project is similar to the project above, this time contributing data from an automatic survey in California, at the world-famous Palomar Observatory. Except here you are looking for supernovae. Exploding stars!
• Galaxy Zoo: Mergers
• Here you are looking for the merging of galaxies. From images you select simulations that look similar to the targeted merger, tuning your best matches. You can even decide which simulation wins in a series of tournament-style competitions.
• Planet Hunters
• Look for extrasolar planets (planets around other stars)! This project finds planets by identifying how the brightness of a star changes over time.
• The Milky Way Project
• This projects aims to sort and measure our galaxy. Using the beautiful infrared data from the Spitzer Space Telescope you are asked to find and draw bubbles. These bubbles identify the life stages of the stars in our Milky Way Galaxy. 
• Old Weather
• This project works to recover worldwide weather observations made by Royal Navy ships around the time of World War I. This will contribute to climate model projections, improve a database of weather extremes, and track past ship movements and the stories of the people on board.
• Solar Stormwatch
• Help spot explosions on the Sun and track them across space to Earth! Not only will you help to identify and classify activity on the Sun but you will also contribute to early warnings if dangerous solar radiation is heading toward astronauts. 

These scientists are seeking to understand a star that has been a mystery for many years. This star is epsilon Aurigae, it is located in the constellation Auriga, and it is a variable star (it changes in brightness over time). This change in brightness is called eclipse. It takes over 600 days, and it only occurs every 27.1 years. The project scientists will guide you through the process of how to observe epsilon Aurigae, how to send them your observations, and then how to see your results, analyze them, and even publish them in a scientific journal.

SETI@home is a scientific experiment that uses Internet-connected computers in the Search for Extraterrestrial Intelligence (SETI). You can participate by running a free program that downloads and analyzes radio telescope data. It is completely safe. All you need to do is download the program and it will run while your computer is on, not disrupting any of your other computing tasks.

CLIMATE SCIENCE

This project works to produce predictions of the Earth's climate up to 2100 and to test the accuracy of climate models. To do this, they need people around the world to give them time on their computers - time when they have their computers switched on, but are not using them to their full capacity. What do you do? Not much really. You to run a climate model on your computer. It runs automatically in the background, not affecting any other tasks for which you use your computer. It is completely safe and requires no more of your time than it takes to download the program. Read more by clicking the image link or go to download the program HERE.

Community Collaborative Rain, Hail and Snow Network (CoCoRaHS) works to measure and map precipitation. Each time a rain, hail or snow storm crosses your area, you take measurements of precipitation from as many locations as possible and report it on the website. These data are compiled and used to provide accurate high-quality precipitation data, increasing the density of precipitation data available throughout the country, and encourage citizens to have fun participating in meteorological science while heightening their awareness about weather.

This project aims to accurately record and analyze "ice on" and "ice off" events as well as snow depth, air temperature, and wildlife observations to learn how climate change affects our environment. You will receive instructions on how to properly IceWatch (even if you live in a warmer climate), you pick your location to observe over the winter (like a nearby lake, bay, or river), record your observations, and submit them online.



GENETICS AND MOLECULAR BIOLOGY

This project is great for gamers!

Genetic sequences are difficult to understand and decipher their structure, and this project aims to compare them to detect any similar regions they may have. So they have put together a website that abstracts the multiple alignment problem to a game where the goal will be to align words made by pieces of different color instead of letters representing the genetic code (A,C,G,T). You create columns of the same color and create gaps, ultimately finding the best tradeoff between aligning color and creating gaps. You can even choose a puzzle to solve from the disease you want to treat.

Another project that is great for gamers. This project is all about protein folding. Proteins are built from individual amino acids but they don't stay all stretched out in a strand, they fold into very specific shapes. Finding the shapes and the optimal folding is the hard part though and is what this project aims to do. Knowing the structures is important to things like drug development and disease research. The problem has been put into game form. You, as the player, solve a series of puzzles to optimally pack you protein, hide the hydrophobic bits, and clear any clashes. You can play individually or form teams, competing with other protein folders around the world.

OCEANOGRAPHY

The whale shark photo-ID library...its cool just saying it. This project uses photographs of the skin patterning behind the gills of each shark and any scars to distinguish between individual animals. This helps scientists to see where individual animals are going, the abundance of whale sharks, and their distribution. If you see a whale shark while out diving you can report all kinds of information about the encounter by filling out their online form, and you can submit pictures to the library.

Do you love whales? All kinds? This project is working to classify the sounds that whales make into distinct regions. "For example, in Orcas (Killer Whales) there are over 150 identified types of call. Every time you match a pair of Orca calls, you're casting a vote for those two calls to be considered 'similar'." The more this is done the better map the researchers get of calls that are alike. This allows them to identify patterns, groups of whales, and eventually get a better understanding of how whales communicate with each other. All you do is look at a spectrogram and listen to a call and then find a matching call. Simple.

This is a project for reporting jellyfish and other marine organisms. If you have seen jellyfish, red tide, or any other unusual marine life you just go online and fill out their form and submit it. They even have a list of similar projects around the world that you can participate in.

FishWatchers is a project out of the International Game Fish Association. This website allows you to  upload your fish observations and photos through the Internet. Any fish any time. This information will then be used to create current distribution maps to assist in monitoring trends in biodiversity

TERRESTRIAL PLANTS AND ANIMALS

This is a great project from a Dutch entomologist that lets motorists report the date, time, and location of their latest outing and the number of insects that get hit (and probably smushed) by their vehicle. Not only does it give an idea about how many bugs are killed by vehicles it provides insect presence in certain locations and information about their flight patterns.

This is a network of people across the United States who monitor plants as the seasons change. It is a national field campaign designed to engage the public in the collection of important ecological data based on the timing of leafing, flowering, and fruiting of plants (plant phenophases). You can send in regular observations or just a single report. Everything is usefull. They provide good identification keys and other tools you will need to start. Not in the U.S.? I'm sure there is is similar project near you.

This is a U.S. based citizen science project that is a national animal and plant phenology observation program. You find out the plants and animals near you on a provided list, learn to select a site and observe and record what is there, and submit your results.

 eBird is a real-time, online checklist program that reports and accesses information about birds. It provides information on bird abundance and distribution at a variety of spatial and temporal scales. It is amassing one of the largest and fastest growing biodiversity data resources in existence. You enter when, where, and how you went birding, fill out a checklist of all the birds seen and heard during the outing, and submit your observations into the eBird database. They even provide tools so you can maintain your personal bird records and even visualize your personal data with interactive maps, graphs, and bar charts.

Neighborhood Nestwatch is a project out of the Smithsonian National Zoological Park and the Smithsonian Migratory Bird Center. The idea is to find and monitor bird nests so scientists can compare how successful nests are in urban, suburban, and rural areas. All you have to do is keep a watchful eye out throughout the year and report your results.

 I know several people that participate in the Christmas Bird Count each year and have a really great time. From December 14 - January 5 volunteers brave the cold weather to do a little bit of bird counting. Anything from feeder-watching to active birding counts. It provides valuable information on migrating birds, bird abundances and distributions, and much more. There are many groups out there too that participate in the count and would love to have another person to help, regardless of your skillset.

 NestWatch, as you might gather from the name, is a nest-monitoring project. It aims to compile large, continent-wide databases tracking survival and reproductive success of a wide range of species and provide a unified nest-monitoring scheme to track reproductive success for all North American breeding birds. You "get certified" (meaning you learn how to properly observe a nest without jeopardizing the nest), look for active nests, monitor the nests and collect data, and enter the data online. The fact that you get to see baby birds should be a big selling point *wink*

The Backyard Bird Count is similar to the Christmas Bird Count in that it is an annual event that provides a real-time snapshot of where the birds are across the North America. The Count occurs from February 17 - February 20 and takes as little as 15 minutes on one day, or you can count for as long as you like each day of the event. When you are finished you enter your results on their webpage.

When it comes to doing science, watching the visitors to your bird feeder sure ain't bad. Project FeederWatch is a winter-long project of birds that visit feeders in backyards, nature centers, community areas, and other locales in North America. By counting birds at your feeder you help scientists to broadscale movements of winter-bird populations and long-term trends in bird distribution and abundance. You count birds at your count site that are there because of something you have provided (plantings, food, or water) and only report the highest number of individuals you see in view at one time, and then you report it online. Simple.

OTHER

 The Quake-Catcher Network (QCN )is a collaborative initiative for developing the world's largest, low-cost strong-motion seismic network by utilizing sensors in and attached to Internet-connected computers. The QCN obtains information about earthquake waves (seismic waves) by using computers that are connected to the Internet. Many laptop computers have built in sensors and desktop computers can utilize small USB sensors to collect the data. The data from these sensors are collected only when the computer is turned on and idle and is sent over the Internet. It is safe and easy. All you need to do is download the program.

 I used to take my ecology lab students out to cemeteries so we could collect data to make life tables. They were always a little squeemish at first but ended up loving the work. The Gravestone Project aims to map the location of a graveyards around the globe and then use marble gravestones in those graveyards to measure the weathering rate of marble at that location. The weathering rates of gravestones are an indication of changes in the acidity of rainfall between locations and over time and could be used as a measure of changes in climate and pollution levels. You go to your local graveyard and take a few measurements such as the lead lettering or headstone thickness.

The bodyLab is a project that researches the evolution of human body shapes and our ideas of attractiveness. All you have to do is go to the website and rate the silhouettes of women and/or men based on if you find that body shape attractive. It is so easy to do you don't even need to create an account.

The Sound Around You is building a sound map of the world as part of a new study into how sounds in our everyday environment make us feel. All you do is use your mobile phones (or another audio recording device if your phone is not compatible) to record 10-15 second clips from different sound environments, or ‘soundscapes’ from a family car journey to a busy shopping center, and to upload them to the virtual map, along with your opinions of them and why you chose to record it.

Dognition is a site that offers dog owners a series of science-based games that determine their dog's unique abilities and their relative strengths and weaknesses in various thinking skills. These skills range from empathy to cunning to memorization. As a user, you enter the results of your dog's behaviors, contributing to a data set that can be used by researchers studying dog cognition. It also offers the owners a "window into [their] dog's mind, offering a first step on the path toward improved behavior." You can tell how your dog sees the world and how they respond in different situations while at the same time contributing to science. Note: As of now this site/service has a fee.

WEBSITES FOR FINDING CITIZEN SCIENCE PROJECTS

This is the best website I have found for finding a project that suits you. It has a great search engine and describes the projects very well. It also includes many local projects as well as great projects for kids.

This site is less detailed and contains fewer projects but is still a good source for citizen science.


(top image from thisgreenblog.com)

The Bite of the Terror Bird

Figure 1. Skull of Andalgalornis steulleti (FMNH P1435).

So you're flipping through various websites and journal table of contents. You come across an article about the feeding behavior of the ancient "terror bird." I think it's pretty clear that you must stop and read it.

Andalgalornis steulleti is a member of an extinct group of large, flightless birds known as phorusrhacids. This group were predominatly a South American radiation of gruiform birds from the middle to lower Paleocene and are most closely related to extant seriemas. Phorusrhacids are called "terror birds" due to their gigantic body sizes, large skulls, and carnivorous lifestyles. The members of this group were ground predators or scavengers that were likely apex predators that dominated their environment in the absence of large carnivorous mammals. A. steulleti lived approximately 6 million years ago in Argentina, it weighed about 40kg, stood 1.4m high, and had a skull length of 370mm. This large, rigid skull was capped with a hawk-like hooked, yet curiously hollow, beak. The feeding behavior of these birds has only been speculated at up till now. This new study performed a biomechanical analysis of the skull using comparative anatomy and engineering (Finite Element Analysis [FEA]) to predict the behavior of the skull. Basically, they looked at the skull itself, compared it to other skulls, and ran it though a CT scanner for analysis.

Figure 2. Stress (Von Mises) distribution of FE models.

Now, if you look at most birds you'll notice that their skulls allow for a lot of mobility between their bones. This gives them light but strong skulls. A steulleti, on the other hand, showed rigid beams in these normally mobile areas. This gave the bird a very strong skull, particularly in the fore-aft direction. The FEA analysis worked with the 3D models created by the CT scans to simulate and compare the biomechanics of biting straight down, pulling back with the neck, and shaking the skull side to side. These are all attack and dismembering motions (lovely). One of the neat things about FEA analysis is that it gives you color images that show areas of low stress as cool-blue and high stress as white-hot (image left). The results from this analysis show that the terror bird was well adapted for driving its beak in and the pulling back. Its marks weren't so high in the shaking side to side motion. Some more comparative anatomy came in when the researchers tested bite force. They had an eagle bite down on a bite meter - bet that was fun to try to do - and they used that information to compare it to the bite of A. steulleti. Pretty close, as they are both large birds with big, hooked beaks. The results showed that the terror bird had a lower than expected bite force that was weaker than the bite of similarly sized carnivorous mammals. This weaker bite force was likely supplimented by the driving down and pulling back motion that they found with the previous test. Overall, behaviorally speaking, the bird probably located prey, stabbed it with its beak and then implimented a repeated attack-and-retreat strategy, puncturing its prey until it was eatable.

Here's the article:
Degrange, Federico J., Claudia P. Tambussi, Karen Moreno, Lawrence M. Witmer, and Stephen Wroe. (2010) Mechanical Analysis of Feeding Behavior in the Extinct 'Terror Bird' Andalgalornis steulleti (Gruiformes: Phorusrhacidae). PLoS ONE: 5(8), e11856. (DOI: 10.1371/journal.pone.0011856)

and...
http://www.sciencedaily.com/releases/2010/08/100818171916.htm

Flying for the Other Team

Growing up I had a friend who owned what we all lovingly referred to as the "incestuous lesbian six-toed cats." In that case it was probably just a of a pair of Hemingway cats getting bored. But how prevalent is homosexuality in the animal kingdom and is there an evolutionary cost (or benefit) to an alternate lifestyle?

A new study published online in the journal Animal Behaviour takes a look at parental care and homosexuality in birds. Homosexual behavior is known to occur in over 130 species of birds, making it a very prevalent but sometimes difficult to explain occurrence evolutionarily speaking (in terms of reproduction and the propagating of one's genes). This study, which pulled together mating and behavior data from multiple studies on 93 bird species, shows that the sex that spends the least time on parental care is more likely to engage in homosexual activity. The results show that same-sex courtship, mounting and pair-bonding are prevalent -- 38% of the species participated female–female sexual behaviour and 82% participate in male–male behaviour. But homosexual behavior accounted for less than 5% of all sexual encounters in the analysis.

These results offer a possible explanation for the evolution of homosexuality. Basically, if you aren't the one taking care of the kids then you have lots of free time for other pursuits, but because you have kids you are still passing along your genes. The cause of the behavior is still unclear - neutral evolutionary by-product or adaptive function? Perhaps its to practice courtship displays, reduce social tension, show dominance, form alliances, gain access to resources, share care-taking responsibilities, or maybe they just think its fun to do when they're bored.

This is the reference:
MacFarlane, Geoff R. , Blomberg, Simon P. & Vasey, Paul L. (2010) Homosexual behaviour in birds: frequency of expression is related to parental care disparity between the sexes. Animal Behaviour: published online. (DOI: 10.1016/j.anbehav.2010.05.009)

...and
http://www.nature.com/news/2010/100709/full/news.2010.344.html

(image from birdsoftt.com)

A Little Patch of Home

Yep, I love me some stories about islands. Have I said that before? Probably, especially considering that's what my masters degree was about. Anyway, this is a new study published in the journal Ecology looking at how land birds colonized the Lesser Antilles.

I can, and have, written long and in depth on this topic, but I'll try to quickly sum up the Equilibrium Theory of Island Biogeography (ETIB). First you need an isolated habitat, island or otherwise -- they are great for study because they are relatively small, replicated, and isolated. The whole formation of a theory thing started when scientists noticed that as the size of a patch increased the number of species increased (not always necessarily the number individuals of a species), this is known as the Species-Area Relationship. Yeah, pretty logical right? Let's keep going with the concept though. Let's say you have a brand new island, species will immigrate to the island -- how many, which ones, and who stays? All that depends on the island itself -- how big it is and how isolated it is from the source population (usually the mainland but also other islands). An island far from the mainland is harder to get to and so has fewer species. A small island is harder to survive on and so also has fewer species. Get where I'm going with this? Now the ETIB says that there is an equilibrium point between immigration and extinction -- a balance between these two processes that determines the number of species on an island. Over time immigration increases the number of species on the island, but as you get more species on an island there are more species that have the possibility of going locally extinct (see the embedded graph).

This study looks at not-so-much the equilibrium point itself, but rather the colonization of island by bird species.

As you might guess, birds are pretty good colonizers, considering that they can fly. But also think about bird species themselves, some are widespread and undifferentiated while others are pretty limited in their distributions and can be rather specific. On islands, because of their size and isolation, this can can mean some species will exhibit morphological or genetic differentiation between individual island populations and/or the mainland source population. This study looks at ecological and geographic distributions of source population to see how recent/continuing colonizers, old colonizers, and non-colonizing/mainland species are different from each other. When you are thinking about these categories, think about them in terms of time and how long it takes a population to genetically differentiate.

In terms of ecological and geographic distribution, the author found that recent colonists tend to inhabit open habitats and are pretty abundant and widely distributed on the islands they are found. Conversely, old colonists tend to inhabit forests and their abundance and distribution depends on the species and on the island. If an old colonist has recently spread to other islands then they act like recent colonists in that they have relatively greater abundance and broader habitat distributions. In general, most of these data showed that the distributions of source populations is broader for recent colonizers than for old colonizers.

To read much more on this topic, here's the article:
Ricklefs, Robert E. (2010) Colonization of the Lesser Antilles by land birds. Ecology: Vol. 91(6), 1811-1821. (DOI: 10.1890/09-0682.1)

(image from birdquest.co.uk and algebralab.org respectively)

Birds of a Feather

After a brief hiatus, in which I was sunburned beyond all recognition (UV rays bad), its back to the sciencey goodness. I figured I would lead off with a story about feather evolution, and if you've been reading this blog then you know that I just love a good feather evolution story. This one was reported on the ScienceNOW website.

It is generally agreed that birds evolved from small dinosaurs about 150 million years ago. As you may already know, the first birds weren't exactly the best fliers. There has been a debate on about how the feathers of these early birds/later dinos were actually used - for gliding or for more sustained flight.

Robert Nudds of the University of Manchester and Gareth Dyke of University College Dublin took a close look at a 100 million year old bird by the name of Confuciusornis. They were looking to see whether or not the feathers of this bird were strong enough to provide both lift and withstand breaking due to rapid flapping of the arms/wings.

They applied Euler-Bernoulli beam theory (or Engineer's beam theory) to this feathery conundrum. This theory is used by engineers to calculate the load bearing strength of structural beams. The thoery was tested out on the bird's primary feathers (outer edge of wing - the big ones) because they bear the most load. After taking lots of measurements of the feathers (diameters, lengths, etc) and combining it with the estimated body weight of the bird, they plugged the values into the Euler-Bernoulli equations. The conclusion: The wings would have buckled under the stress. The same analysis was performed on the older (140 mya) Archaeopteryx. It also failed.

Other scientists are not completely sold on these conclusions. They cite examples of fossils found in lake and marine sediments, saying that some flight (rather than simple gliding) took the birds to those distances. Also, fossilized feathers can be difficult to measure accurately which could affect the results of the calculations.

The story link:
http://news.sciencemag.org/sciencenow/2010/05/did-first-feathers-prevent-early.html

(image from http://www.toyen.uio.no/palmus/galleri/montre/english/161_632.htm)