Friday, August 31, 2012

Hagerman Wildlife Refuge: Part 3

Bottomlands of Hagerman National Wildlife Refuge.
Hagerman National Wildlife Refuge is notable for its location within the Central Flyway. It is an active site for migratory resting and winter habitation for a number of birds, especially waterfowl. This time of year serves as the transition period for many bird species. Some like the Painted Bunting leave before August is even over, while the local Cliff Swallow colonies start fattening up on insect swarms before migrating at the end of September. During midsummer the species count is often over one hundred, but during migratory periods it easily exceeds that.

Wednesday, August 29, 2012

Great Blue Heron

Great Blue Heron, Ardea herodias
The Great Blue Heron can be seen year round for the majority of the United States, in parts of southern Canada in the summer, and throughout Central America during the winter. It is the largest of the North American herons which can be found in a large variety of both saltwater and freshwater habitats. Their prey involves anything they can strike and catch as they slowly wade through the deep waters. With a high percentage of rod-type photoreceptors, this heron can hunt during either the night or day. This widespread aquatic species has become important as a biomonitor for ecosystem contamination. The Great Blue Heron has a a high trophic position and low sensitivity to organochlorine contaminants. This allows for contaminant accumulation, but without the immediate adverse effects. Due to their size, the Great Blue Heron has few predators, the majority of which are large raptors.

Monday, August 27, 2012

Purple Martin

♂ Purple Martin, Progne subis
The Purple Martin is the largest of the North American swallows, and one that breeds almost entirely in backyard birdhouses. Before the arrival of Europeans, some Native American tribes had set up empty gourds for this bird to use. An almost complete conversion from its natural use of abandoned woodpecker holes to those artificially manufactured occurred along the east coast before the beginning of the twentieth century. West of the Rocky Mountains, where the species is less common, there have been some sightings of nesting in natural cavities. They compete for space with the introduced European Starlings and House Sparrows. The use of colony site management helps prevent area extinction of the Purple Martin. This insectivore can be seen nesting in North America during the summer, and wintering in the savannas and agricultural fields of South America.

Friday, August 24, 2012

American Pika

American Pika, Ochotona princeps
Found within the order Lagomorpha alongside rabbits and hares, the American Pika can be found in alpine regions of the western United States and southwestern Canada. They live near mountain meadows on rock faces, cliffs, and rocky areas known as talus. Their diet is composed of grasses and herbs which pikas cut and dry to form hay piles for winter consumption. This densely furred species does not hibernate. Instead, they spend most of their time in their den during winter along with the rest of the colony.

Unfortunately for the American pika, they have become a symbol of global warming. The threat of climate change not only threatens this species arguably more than the polar bear, but they may be among the first to extinction. Already living at a high elevation, the pika has no place to migrate to when temperatures rise. A den does not mitigate extreme temperatures like a burrow does, nor has the American pika evolved to migrate large distances. The curing of vegetation, a period of high activity, would occur during hotter temperatures which could create direct thermal stress on a creature that cannot dissipate heat easily.

Studies on climate change and the American pika are still conflicting. This may be due to the lack of many long-term studies. As this species lives in isolated colonies, there is some hope that a complete extinction will not happen. The effects of global warming on sensitive species such as the American pika have been gaining more attention and more monitoring. This not only allows better prediction for the survival of this species, but others like it as well.

Wednesday, August 22, 2012

Orb Weaver Family

Juvenile Orb Weaver, Araneidae
Associated with the classic orb web they weave, the Orb Weaver family is spread throughout the world. There is great variation in size and appearance within the Araneidae family and significant distinction between genders. While the smaller males wander to find a mate, the larger, and often more colorful, female spins her web. If prey is abundant and good support is to be found, the orb weaver will spin a web in any habitat. Most sightings occur in summer or fall when adults reach their largest size. Although they can be sizable and extraordinary in appearance, these spiders are quite docile and non-aggressive. A bite most often occurs due to provocation, posing only a threat of a bacterial infection. Charlotte A. Cavatica of Charlotte's Web is a barn spider, a member of the orb weaver family.

Monday, August 20, 2012

Bare-throated Bellbird

video
Sounds of the Bare-throated Bellbird, Procnias nudicollis

Known as one of the loudest birds in the world, the male Bare-throated Bellbird is a brilliant white bird found within the Atlantic Rainforest. The call itself is a result of extreme sexual selection where the less striking female lacks the far carrying metallic cry. This rapidly declining species is currently listed as vulnerable on the IUCN Red List category. The reason is not only due to the increased rate of habitat loss, but also the more intense trapping pressures as its call and plumage make it a popular demand for a caged bird.

They are still quite common in Brasil near Parque Estadual Turístico Alta Ribeira, also known as PETAR, where this video was shot. While quite easy to hear, spotting one is surprisingly hard.

Friday, August 17, 2012

Wildfires

Remains after controlled burning in Australia.
As mentioned before, wildfires are vital to the health of many different ecosystems. They provide control, allowing the adaptive species a higher chance to flourish. They also promote the composition of the forest and encourage biodiversity in various ways. The media will likely always focus on the destruction of these fires, but while human influence has changed this once natural phenomena, wildfires do still have an important purpose.

I know I've probably already exhausted this topic, but as wildfires are in the news again, a reminder seems like it wouldn't hurt. Besides, I really wanted to share this photo as it is one of my particular favorites of all my fire-related shots.

Wednesday, August 15, 2012

Mantis II

Possibly a Carolina Mantis, Stagmomantis carolina
As previous mentioned, the mantis is a well adapted predator. The rapid movement of their forearms allows for quick capture of prey within their attack zone. The success of a capture relies heavily on the compound eye which allows for spatial vision. Through what is known as peering behavior, a mantis can estimate the distance to an object. This behavior minimizes unnecessary movements which is essential  in foraging and protection.

Mantis are very aware of their surroundings. This particular mantis only allowed for a short impromptu photo session before jumping onto the phone.

Monday, August 13, 2012

Primate Hand Dominance

Prosimian Ring-tailed Lemur, Lemur catta
The trait of hand dominance, particularly the bias towards right-hand dominance, is quite unique to the human population. While only 10% of the human population is left-handed, the rest of the primate family has an even ratio of left-handed and right-handed dominance. The hand preference may be trained for some species or acquired by other means, but the inborn hemispheric asymmetry is limited to humans.

Happy International Left-Handed Day!

Friday, August 10, 2012

Sun and its Significances

Sunset over the Rocky Mountains.
The influence the Sun has had not only on evolution, but also human culture is astounding. While the importance of the Moon is not clear to many, the life giving rays of the Sun are and have been for millenia. The tremendous mass of the Sun allows for the fusion of atoms. It is this process that generates the energy to sustain life on Earth in the form of ultraviolet radiation, visible light, and infrared radiation. Neither a liquid nor solid, the Sun is composed of a number of gaseous layers. The lower density photosphere is where most visible light originates from and is often referred to as the "surface" of the Sun. The less dense, dim layer above the photosphere is called the chromosphere. This layer can only been seen with special filters or during a total solar eclipse where the photosphere is blocked. While the temperature drops between these two layers, from 5800 K to 4000 K, the temperature rises to about 10,000 K at the top of the chromosphere. Between the chromosphere and the corona, the outermost region of the Sun's atmosphere, is a section known as the transition zone. This zone is where the temperature skyrockets up to 1 million to 2 million K. The rise in temperature is due in part to the highly ionized elements found in the corona.

The Sun has received much reverence, but for a star it is quite average. In stellar classification, the Sun falls in with main-sequence stars. The Balmer-based spectral types are arranged by surface temperatures for the OBAFGKM sequence where O is the hottest and M is the coolest. Classification is then broken up further into ten temperature subdivision. These are designated by integers where 0 is hottest, and 9 is coolest. As a G2 spectral type, the Sun is grouped with the common main-sequence stars of M, K, and G. Compared to other stars, the Sun also has an average mass and a lower luminosity. Still, from the cultures of the ancient Egyptians to that of the Chinese, the ancient religions of Greece to those of modern day, the Sun remains an inspiration.

EDIT: I was recently shown this article on the Sun and the argument that it is not truly average. It's an interesting read and perspective, and as I have way fewer credentials, I don't think I rightly can disagree; however, I will say perspective is everything. This focuses on mass present day. There is little mention to the fact that giants and supergiants have very short lifespans especially compared to red dwarfs and brown dwarfs. I had been taught that we still haven't a clue as to the life cycle of brown dwarfs and red dwarfs because they have such an exceedingly long life. I'm personally curious as to how the Sun would match up compared to all the giants, supergiants, brown dwarfs, and red dwarfs that ever existed. Either way, looking at different perspectives is important, as is giving others the ability to see it!

I'm pretty sure I'll be bringing up more astronomy here in the future. While I try to keep posts a relatively nice length, there is still much left unsaid and other topics and photos left untouched.

Wednesday, August 8, 2012

Moon and its Influences

View of the Moon just before Sunrise.
The Moon has been a revered object throughout human history from myths and rituals to romances and stories. While the impact the Sun has had on the evolution of life is knowledgeable to most, the role the Moon has played is less so. The tides of the ocean are created due to a combination of the Sun and the Moon, but it is the Moon that impacts tide activity the most. Without a moon, the tides would be smaller, minerals would wash into the ocean slower, and life would take longer to establish. In this moonless condition, the Earth would be spinning much faster causing high, continuous wind. This wind would lead to enormous, constant waves. In these conditions, the transition of life from ocean to land would be extremely difficult to achieve. Life has evolved in extreme settings before, and might then, but it would have more challenges: perpetual winds and regular debris. A number of animals relay on the moon not only for hunting, but also reproduction.

The rapid rotation would also mean a different circadian rhythm as the 24-hour day becomes close to a 6-hour day. A rapidly rotating terrestrial planet is also highly unstable without an anchor such as our Moon. The significant wobbling would cause enormous stress on the surface of Earth. This would result in large magnitude earthquakes, high volcanic activity, catastrophic tsunamis, an unstable atmosphere, and drastic magnetic field changes. The evolution of both Earth and life on it are not just the result of the perfect distance from the Sun, but also the stabilization that the Moon has given our planet.

This week I've decided to just continue with an astronomy theme.

Monday, August 6, 2012

Jupiter and its Moons


Jupiter with Ganymede and Europa minutes after Io is eclipsed.
Jupiter, the most massive planet in our solar system, contains a current count of 50 "permanent" moons. Of these many moons, the four largest are Callisto, Europa, Ganymede, and Io. These four are known as Galilean satellites, having first been observed and recorded in 1610 by Galileo Galilei. Europa is thought to have a liquid ocean under its frozen crust, but the possibility may also lie with Callisto and Ganymede. Ganymede is also the largest planetary moon and the only moon with its own magnetic field. Io, on the other hand, is the most volcanically active body in the solar system.

Another capture of Jupiter, Ganymede, and Europa.
The Great Red Spot is not the only interesting feature of Jupiter. The rings of Jupiter were first discovered in 1979 by NASA's Voyager 1 spacecraft. These are a flattened main ring, an inner cloud-like "halo" ring, and a third gossamer ring. The gossamer ring, call such due to its transparency, is actually three rings of microscopic debris. That debris came from the three small moons Amalthea, Thebe, and Adrastea. Perhaps the most interesting fact of Jupiter is that is can technically be called a failed star. It lacks the mass needed to graduate to a brown dwarf and has cooled below the threshold for fusion; however, enough heat, mass, and pressure remain to cram together atoms resulting in new behaviors. With this limbo state of chemical and nuclear reaction, oddities such as liquid metallic hydrogen are possible. It is with the launch of and arrival of Juno to Jupiter that we may finally see below the clouds of Jupiter.

As a celebration for the successful landing of Curiosity, I decided today was a good day to share what may be my favorite photo I've ever taken. It was with the aid of a wonderful astronomer and telescope during an amateur astronomy night in Australia that I had this opportunity, and success.

Friday, August 3, 2012

Cerrado Soil

Aluminum red soil is a characteristic sight of the Cerrado.
As mentioned on a previous post, the soil in the Cerrado of Brazil is a unique composition. The characteristic red coloration is due to a high concentration of aluminum and iron oxides. While this is toxic to most cultivated plants, native species are resistant to the toxicity of aluminum. Even with the poor soil, the Cerrado is a biodiversity hotspot. The climate of the Cerrado, moist during the rainy season, and hot year round, weathers the soil leeching out all but the most resistant minerals. As the soil also has low nutrients, it previously went uncultivated. The rise of fertilization use has resulted in great development in the area. It is now one of the most threatened ecosystems, even more so than the Amazon.

Wednesday, August 1, 2012

Zebra Tarantula

Zebra Tarantula, Aphonopelma seemanni
Quite recognizable by the distinct leg markings, the Zebra Tarantula originates from Costa Rica. The feet of spiders have thousands of spatulate hairs that generate van der Waals forces as a dry attachment system. There are also small distal claws to enhance adhesion, interlocking with substrate on a rough surface. The zebra tarantula in particular has an additional ability to use its silk on its feet for adhesion. Whether this silk may or may not be produced by spinnerets on the legs is in question, but this ability is relatively unique to this particular species.