Lightning

Compilation of lightning strikes in the Rocky Mountains.

As clouds grow, the ice particles within collide, fracture, break, and acquire charge. The larger particles are thought to gain more negative charge while the smaller particles acquire a more positive charge. Gravity, updrafts, and other influences separate the particles leaving the lower portion of the cloud more negatively charges and the upper portion with positively charge particles. Lightning is an electrical discharge from the enormous electrical potential between positively and negatively charge particles.

There are number of different types of lightnings. One of the best known, and most dangerous, is cloud-to-ground lightning; however, intra-cloud lightning is the most common type of discharge. The charge is usually restricted within the same cloud, but not always.

While fatalities by lightning are rare, life-long health concerns, including heart and lung damage, are more common. Lightning safety is important to know, especially if the hairs on your neck begin to stand on end. Always seek shelter during a storm, but if it is unavailable, crouch down into a ball with only your feet touching the ground (in other words, do not lie down).

Upcoming

Red Fox, Vulpes vulpes

Sorry for the delays the past week. Although I will likely take a brief hiatus next week, I am planning an interesting post for this Thursday. Until then, here's another photo from my trip in Colorado. I will be following through with more on red foxes the first week of January!

Halos

Partial Solar Halo

The phenomenon of a circle of light sometimes spotted around the sun or moon are known as halos. These are caused by the refraction and reflection of light on ice crystals in the upper atmosphere. High, thin cirrus clouds are made of millions of ice crystals in the upper troposphere, part of the atmosphere almost always below freezing, and are a reason these halos. While a halo can therefore be seen year-round, the descent of the northern jet stream southward from fall to spring brings even more of these ice crystals into the air.

Wildlife Rehabilitation

Eagle properly being rehabilitated by Beverly Grage.

Wildlife Rehabilitation, as mentioned before, is an expensive and time consuming volunteer position, but also a priceless possibility for wildlife to have a second chance at life. To be a wildlife rehabilitator requires permits from the state at minimum, the federal government as well at maximum. It is not, as many think and have done, a simple task to properly raise wildlife, and it is also illegal without permits. Clearing up some misconceptions may help illustrate why rehabilitation is highly regulated and requires experience.

1. There is often confusion as to what imprint and domestication are, and why they are not similar. A domesticated animal is one that has been bred for hundreds, and even thousands, of years to live with humans. An animal that is imprinted is NOT domestication. Imprinting is an animal who has no fear of humans, creating a danger for the person and the animal as the animal is still wild. The job of a rehabilitator is to keep a fear of humans in the animal and let them remain wild. That is how they will survive, both humans and in the wild where they belong.
2. Wild animals are wild animals. That has not been bred out of them. Always remember wild animals are unpredictable no matter how tame they seem. Adorable babies grow up to seek mates, and nothing will stand in their way to pass on their genes.
3. If the animal cannot be re-released, there are only two options: placement or death. Know that an imprinted animal cannot be released into the wild. One of the most unfortunate parts is how many animals lose their lives from careless humans. Sanctuaries are a last resort for the animal, but all sanctuaries have limited caging to house these animals, for their safety and for humans. 

A wildlife rehabilitator only releases an animal that has a chance of survival. They are trained to equip those animals with the skills necessary for survival, including a fear of humans. That is why, unless you have the proper permits and training, call a wildlife rehabilitator as soon as possible if you find an injured, sick, or orphaned animal. Even a day's delay can result in imprinting, and unless they can then be placed, the wait could be their death.

Wildlife Rehabilitation

Eagle Release with Beverly Grage

Wildlife Rehabilitation is one of the most underappreciated and solely funded volunteer positions. These individuals go through rigorous obstacles and training in order to provide injured, sick, and/or orphaned wildlife a second chance at life. In addition to hours of dedication, they must go through hoops to even obtain the permits ranging from state permits for mammals to federal permits for birds. Not everyone can rehabilitate as not everyone knows how to properly prepare an animal to live in the wild.

Most wildlife rehabilitators have no funding, but rely solely on donations. For many, the majority of costs from food to veterinarian visits to housing come out-of-pocket. For this #givingtuesday , why not consider a wildlife rehabilitator?

One wildlife rehabilitator I ask you to consider donating to is Beverly Grage. She has helped everything from opossums to eagles, a privilege few are allowed. Raptors are one of her specialties with high rerelease rates, but unfortunately, they are also one of the most expensive. With the majority of raptors having their primary food as mice, cost to feed can easily exceed $1000 a month with less than 30 raptors. Often, it's more than 30 being cared for. With a rate of more than a raptor a day during baby season, the cost can be astounding. But for a second chance at life, wildlife rehabilitators like Beverly think it's worth it and so do her donors. Remember, even $1 can make a difference!

You can learn more, and possibly donating to Beverly Grage, from her site. You can learn of other Texas rehabilitators by visiting the TPWD website. You can usually learn about wildlife rehabilitators in other states by visiting that state's parks and wildlife website.

On the following post I plan to clear up a few misconceptions such as how imprinting is not domestication, why wild animals will never make a good pet (not to mention it is illegal), and how wildlife sanctuaries are providing a chance when rehabilitation fails.

Happy Thanksgiving

Wild Turkey(s), Meleagris gallopavo

Taking a short hiatus this week for Thanksgiving, but you can always refresh your knowledge on Wild Turkeys and Australian Brush Turkeys from the posts last year. See you next week!

Longlegged Flies

Condylostylus preying on Aleyrodidae

Longlegged flies of the family Dolichopodidae are true flies found worldwide in a variety of habitats. While their appearance varies, the adult flies generally have metallic colored bodies, long legs, and veined wings. Some larvae are predators while others mine plants, but all adults feed on small insects including whiteflies. Evidence of their existence dates back to the Cretaceous Period as many have been found in amber deposits.

An earlier post I wrote on Google+ briefly looks at the relationship between the longlegged fly genus Condylostylus and Aleyrodidae, also known as whiteflies.

Whiteflies

Whitefly, Bemisia

Whiteflies feed on the sap of plants, similar to the closely related aphids, mealybugs, and scale. They are most active during the warm parts of the day and prefer the undersides of leaves. Often confused for miniature moths, they are hardly 3 mm (1/8 inches) in length yet can become a serious pest when natural biological control is disrupted. They build up populations quickly and can breed all year in warm climates, and warm environments such as greenhouses. Greenhouse whiteflies and the sweetpotato and silverleaf whiteflies have a wide range of host plants and are the most common whiteflies to cause damage.

Rock Rose

Rock Rose, Pavonia lasiopetala

Rock Rose, also known as Rose Mallow, Rose Pavonia, Wright Pavonia, and Texas Swampmallow, is a native flower of the mallow family, Malvaceae, and can be found in Texas and Mexico. It is a highly versatile plant that can tolerate partial shade, numerous soil types, drought, and heat. Although it only lives for 3 to 6 years, it regularly and easily self sows its seeds. Similar to the another native shrub, Autumn Sage, rock rose will bloom from April to November. The foliage provides dense cover for wildlife as well as browse, the seeds are food to a number of game birds and small mammals, and the flowers are a favorite among many pollinators including hummingbirds.

Cellar Spiders

Cellar Spider, Pholcus phalangioides eating a cricket.

Cellar spiders of the Pholcidae family are spiders that wait for prey to entangle in their web and are often confused for a brown recluse. They have a number of other common names including vibrating spider and daddy long-legs spider. They are most often referred to as cellar spiders due to their preference of habitat of dark, damp places such as in basements and crawl spaces. When these spiders feel threatened such as when large prey disturb their web, they start vibrating vigorously back and forth. While the reason for this is not specifically clear, current thought points to the spider being harder to focus on, and therefore, harder to catch. The most confusing of the common names, daddy long-legs, has been used for cellar spiders due to their long legs, but also to a non-spider arachnid of the Opiliones family, also known as harvestmen. Contrary to popular thought, neither of these specimens contain venom that is fatal to humans. Harvestmen do not possess venom nor even have a means of deliver, and cellar spiders have only mild venom that cannot even be effectively injected into humans.

Texas Brown Snake

Texas Brown Snake, Storeria dekayi texana

The Texas Brown Snake is a subspecies of brown snake, a group of small, nonvenomous snakes. Brown snakes can be found throughout the central and eastern portion of the United States. They can be found in a range of habitats including woodlands, open prairies, marshes, and debris piles. Their diet consists of a variety of prey including earthworms, snails, and slugs, and so they are also often found in gardens. They rarely grow beyond 30 cm (12 in) and are best keyed out by their keeled scales.

Virginia Creeper

Virginia Creeper, Parthenocissus quinquefolia

Virginia Creeper is a native woody, deciduous vine often confused for poison ivy. It can be found throughout the eastern portion of North America and is relatively adaptable, tolerating shade, salt, and dry conditions including coastal dune areas. During the fall, the five leaflets turn brilliant shades of red. A variety of wildlife eat the autumn fruits including songbirds and small mammals, while the foliage is often consumed by both deer and cattle; however, the berries are highly toxic to human consumption mainly due to oxalic acid. The common name Virginia creeper comes from  the creeping tendrils to allow it to climb. Although great cover for many small animals, this vine can become parasitic and kill its host plant overtime if left unchecked.

Leaves of three, let it be;

Leaves of five, let it thrive.

While Virginia creeper and poison ivy often grow in the same locations, looking at leaflet number can help distinguish the plants. A brightly colored leave in fall could be either, but if it has five leaflets, it's Virginia creeper, and therefore harmless.

Gulf Fritillary

Gulf Fritillary, Agrulis vanillae incarnata

Contrary to its common name, the Gulf Fritillary is not a true fritillary butterfly and not closely related to them. Whether separated with the long-butterflies, Heliconiidae, or included with the brushfooted butterflies, Nymphalidae, the gulf fritillary is the only one of the Agraulis genus. These butterflies can be found throughout the southern United States down to South America. One of their main host plants are passionflowers which provides food for the larvae and nectar for the adults.

Purple Passionflower

Purple Passionflower, Passiflora incarnata

Purple Passionflower, also known as the Holy-Trinity flower, Maypop, White Sarsaparilla, and passion vine to name a few, is a native perennial vine found along the southeastern portion of the United States. The unique, showy flowers bloom generally June to October. Butterflies and hummingbirds are attracted to the flowers, and the young tendrils are a favorite of wild turkeys. There is an extensive history with human consumption as well. The fruits, nicknamed maypop, were eaten raw, made into juice, or boiled into syrup while the young shoots and leaves were eaten with other greens by Native Americans. The roots were made into a tea used for inflammation, to aid in weaning, and to treat liver problems to name a few ailments. It is still in practice today to help treat anxiety and insomnia as well as gastrointestinal upset and to relieve symptoms of narcotic drug withdrawal.

Blazing Star

Blazing Star, Liatris

Blazing Star, or Gayfeather, are tall, tufted flowers of the Liatris genus within the Aster family. They can grow anywhere from 1 to 3 feet on average, although species such as Prairie Blazing Star are known to reach 5 feet in height. These plants serve not only as a popular and important food source for many butterflies, but as a preferred browse for deer and antelope and a source of seed for birds. Often the absence of blazing star is a good indication of heavy grazing pressure within a field. Many American Indian tribes also used certain species of blazing star for consumption, from baking the sweet roots over fire to boiling the entire plant to treat heart pains, diarrhea, or inflammation.

Western Interior Seaway

Scallop, Kingena wacoensis and Brachiopod, Neithea texana
[Grayson Formation, Lake Arlington, Texas]

The Western Interior Seaway was an extensive epeiric sea formed from the high sea levels between the middle and late Cretaceous Periods over 75 million years ago. It once covered most of the Midwest of North America with many present day states once completely submerged. A vast number of marine fossils, from vertebrates to molluscs, have been unearthed in these regions.

Devil's Toenail, Exogyra ponderosa
[Anacacho, Uvalde County, Texas]

The widespread and well-preserved fossils of marine fauna has allowed for the environment of the Western Interior Seaway to be determined. For the majority of its existence, water column stratification gave way to dysoxic to anoxic bottom-water environments. These conditions led to a number of opportunistic and low oxygen adapted taxa to emerge. There was also a predominance of brackish-water conditions on the surface. As the inland sea stretched from the far north down to the tropics, there was a mixing of cooler, less saline waters with warm tropic waters resulting in a limited presence of typical marine organisms.

Lobsters

A lobster is an invertebrate with a hard, protective exoskeleton. They need to molt in order to grow, a process that may change the color of the animal in some species. Their unequal claws can be categorized as the smaller ripper claw to tear soft flesh and the larger crusher claw to pulverize shells. While the claw types can be either left or right, males generally have larger crusher claws than females.

Clawed lobsters belong to the family Nephropidae. They have existed at least since the Cretaceous period over 140 million years ago; however, the ancestor of lobsters and scorpions, Kooteninchela deppi, has fossil records spanning at least 550 million years. During the Cretaceous period, at least 53 species existed whereas during the Tertiary period, only 18 species have been identified. Currently, at least 29 species exist and have been recorded worldwide.

Tomorrow, October 16th, 2013, is National Fossil Day. As I only post twice a week, and not on Wednesdays, I declare this fossil week where I'll post my final fossil pictures - until the next batch :)

From the newest fossil collection at the Heard Natural Science Museum and Wildlife Sanctuary.

Passenger Pigeon

Passenger Pigeon, Ectopistes migratorius

The Passenger Pigeon was once famous for the sheer number of pigeons in a single flock, and is now famous for a human caused extinction. These birds once blotted out the skies of the eastern portion of the United States. John James Audubon once estimating a single flock containing over 300 million birds. Unfortunately, they were highly marketable and there were no laws to protect them in the 1800s.

Stool pigeon is a term derived from these birds as hunters would mount a live passenger pigeon on a stool. This pigeon would then cry to its brethren for help allowing for easy prey. A famous hunt in Petoskey, Michigan in 1878 recorded at least 50,000 kills each day for nearly five months. By the time regulations were finally in place, too many had been killed and too much habitat removed for passenger pigeons to ever recover. While there were still thousands in the wild, they were no longer in a situation where they could breed, and passenger pigeons slowly died off. The species was officially declared extinct in 1914 when Martha, that last living passenger pigeon known who lived at the Cincinnati Zoo, died.

”It is not always necessary to kill the last pair of a species to force it to extinction.” - Paul R. Ehrlich

In the late 1800s, the Lacey Act was established in part due to the nearing extinction of passenger pigeons at the time. The law prohibits illegally obtained game to be shipped across state boundaries. In 1918, the Migratory Bird Treaty Act was passed to protect all native birds to the highest degree. By federal law, one must have a permit to possess any native bird or bird parts including, but not limited to, feathers, nests, mounts, and eggs. While the lessons of the passenger pigeon extinction have not been learned everywhere around the world, there has been progress in species protection.

For another, slightly different write-up I've done on Passenger Pigeons, you can see my Google+ post. This beautiful, preserved mount is currently on display at the Heard Natural Science Museum and Wildlife Sanctuary.

Prairie Sunrise

Sunrise on the Prairie

Busy week, so here's a simple photo of sunrise on the prairie. I'll be back to posting as usual next week!

Cactus Coreid

(Instars) Cactus Coreid, Chelinidea vittiger

Cactus coreid are a type of insect found throughout most of North America, and in parts of Australia as biological control agents. They rely on prickly pear cacti and are often considered pests. These highly host specific insects lay their eggs on the underside of Opuntia species, and the nymphs reside upon the same plant for their entire life. One species in particular, Chelinidea vittigera, was noted to starve rather than find a new host plant upon the destruction of its original host plant. On the other hand, they prefer plants damaged by fire for mating, feeding, and resting, but not as oviposition sites. The reasoning is contributed to the presence of protective spines on undamaged cacti compared to the burned cactus.

Longhorn Beetles

"Sharp-rumped Beetle", Neoclytus mucronatus

Longhorn beetles, characterized by their long antenna, are of the family Cerambycidae. Within this family, over 412 species have been identified in Texas, over 1000 species in North America, over 10,000 species in the Western Hemisphere, and close to 20,000 species worldwide. They can be found in a wide variety of habitats, but generally feed on dead, dying, or decayed wood if not living plant tissue. Those classified as girdlers will sever branches to allow larvae to develop within the distal portion of the branch. In the adult stage, their food preference ranges from flowers and sap, to bark and fungi, to no nourishment beyond water. A longhorn beetle may live anywhere between 1 to 3 years, but general spends most that time within the larval stage.

Scarlet Morning Glory

Scarlet Morning Glory, Ipomoea hederifolia

Scarlet Morning Glory, also called Scarlet Creeper, is an annual vine that blooms starting mid-spring up through fall. It is a native member of the morning glory family that attracts bees, butterflies, and hummingbirds. Preferring moist hammocks, thickets, and disturbed sites, this plant can be found throughout most of the southern United States and is currently listed as invasive in Hawaii. Although parts of scarlet morning glory are toxic, the roots were once used medicinally.

Bluestem Prickly Poppy

Bluestem Prickly Poppy, Argemone albiflora

Bluestem Prickly Poppy, also known as White Prickly Poppy, is an annual or biennial flower that has a deep taproot and preference for limestone based soils. It may bloom starting mid-spring up until early fall. The prickly leaves, for which it gets it common namesake, results in this flower being a common find in fields as cattle will not eat it. While quail and other birds love the oily seeds, all parts of the plant do contain toxins in the form of alkaloids.

Hyaenodon

Hyaenodon [Brule Formation, Pennington County, South Dakota]

The genus Hyaenodon contained carnivorous mammals that lived from the Eocene Epoch 42 million years ago until extinction during the Oligocene Epoch 25 million years ago. There so far are records of at least 30 species with fossils found in Asia, Africa, Europe, and North America. Hyaenodon means "hyena-toothed" as these animal had large, sharp teeth for their carnivorous diet.

Teeth of the Hyaenodon

During their existence, Hyaenodon was a dominant predator. The species ranged in size from small and fox-like to others as large as rhinos. It is believed the smaller species hunted in packs, likely at night, whereas the larger species likely hunted alone. Extinction of the order Creodonta, of which Hyaenodon belongs, possibly came from competition with Carnivora, the order most carnivores belong to in modern times.

From the newest fossil collection at the Heard Natural Science Museum and Wildlife Sanctuary.

Merycoidodon

Merycoidodon cuibertsoni [White River, Dawes County, Nebraska]

Related to camels, sheep, and pigs, Merycoidodontidae were mammals that once roamed North America 34 million years ago until their extinction 5 million years ago during the Tertiary Period. Their teeth contained long-lasting grinding surfaces well adapted for effective side to side chewing. They were about 1.2 m (4 ft) in length with a heavy build similar to modern day pigs. Fossils of Merycoidodon have most often been found in large numbers in small areas pointing towards the likelihood of these creatures having lived in herds.

From the newest fossil collection at the Heard Natural Science Museum and Wildlife Sanctuary.

Prairie Ring-necked Snake

Hatchling Prairie Ring-Necked Snake, Diadophis punctatus arnyi

The Prairie Ring-Necked Snake, a subspecies of ring-necked snake, is a small, non-venomous snake. They range in size between 25-38 cm (10-15 in) and have a distinctive orange or yellow neck band as well as an orange or yellow belly. Although found throughout the eastern two thirds of the United States up into Canada and down into Mexico, they are secretive. Ring-necked snakes prefer rocky, wooded hillsides for shelter and to search for prey. Their main diet consists of worms, slugs, other soft-bodied insects, and small reptiles. These snakes do not reach sexual maturity until the third year and are thought to have a lifespan close to 20 years in the wild. They rarely venture out during the day and have a single denning site.

Labor Day

Due to some technical difficulties, there will be no post today. Hope you had a great Labor Day Weekend!

Mastodon

Molars of Mammut americanum, Oklahoma.

Related to elephants and extinct for close to 11,000 years, mastodons were one of the megafauna that once inhabited North America. They were similar to modern elephants with large, curved tusks and corrugated grinding surfaces of the teeth, but they were also similar to mammoths with their shaggy hair. Remains of mastodons were first discovered in 1705 when a tenant farmer discovered a five-pound tooth. More teeth were discovered in other parts of North America until a French anatomist finally gave mastodons a name. The common name was based on the teeth as the conical cusps resembled breasts: mastos (Greek for breast) and odont (for tooth). Although the shape of the tooth first gave thought to flesh-eating beasts, it has since been concluded that the shape of the teeth provided best for browsing and grazing.

From the newest fossil collection at the Heard Natural Science Museum and Wildlife Sanctuary.

Sharks

Fossilized Shark Tooth

Sharks have been in existence since at least the Ordovician Period over 450 million years ago. This was during the time of vast marine diversity, and little diversity present on land. One of the earliest representations of sharks discovered was Cladoselache, which differs in form from modern sharks, but was still a high-speed predator. The most common discovery related to ancient sharks are their fossilized teeth. As sharks shed thousands of teeth throughout their lifespan, there is a higher chance for one of these teeth to find the right conditions for fossilization; however this often presents a problem of identification. In addition to scattered and mixed teeth findings, many sharks exhibit dignathic heterodonty, or a difference in the upper and lower teeth in addition to parasymphyseal, or a difference in teeth in relation to jaw position. Gender difference are also often translated to the teeth making it hard to identify the species a shark tooth originated from.

From the newest fossil collection at the Heard Natural Science Museum and Wildlife Sanctuary.

Lynx Spiders

Lynx Spider, Oxyopes acleistus

Lynx spiders of the family Oxyopidae are found throughout the world, particularly in the tropics and subtropics. These spiders are active, roving hunters often using foliage for camouflage to ambush prey. Some species can jump up to 2 cm (.79 in) in the air to catch insects in flight. Although lynx spiders usually do not build webs, there are exceptions. These spiders are also very protective of their eggs, and often die of starvation due to this behavior.

Cottontail Rabbit

Camouflaged Eastern Cottontail, Sylvilagus floridanus

The cottontail rabbit is a genus of rabbits, Sylvilagus, with sixteen species. The most commonly spotted, and the one with the widest distribution, is the Eastern Cottontail. Although coloration may vary between species, all have the distinct "cotton ball" tail. These animals can live in a wide variety of habitats and eat a wide variety of foods. They mainly feast on grasses and herbs, but often find their way to gardens. Rabbits may breed up to four times a year, and babies are on their own in three to four weeks. It is important to note that the mother rarely stays with her young, but that does not mean she has abandoned them.

A short break from fossils due to a busy week, but they will return next week!

Sea Urchins

Extinct Sea Urchin, Sinaecidaris tauozensis [Taouz, Morocco]

Sea Urchins, of the class Echinoidea, are a type of echinoderm, much like brittle stars and jimbacrinus. Echinoderms, of the phylum Echinodermata, existed Precambrian over 600 million years ago. They have only been found in marine waters with 6,000 species still in existence. They are characterized by a well-developed water vascular system and by their mesodermal skeleton.

Extinct Pencil Urchin, Acrocidaris nobilis [Jurassic Period/LaRochelle, France]

Of the thousands of species of echinoderms, only about 700 species are sea urchins. As with most within the phylum Echinodermata, adult sea urchins have a fivefold symmetry called pentameral. They have characteristic long spines and a spherical shape. These spines serve not only as protection, but also as a way to move and a habitat for other creatures such as fish. Sea urchins feed on organic matter with one of their primary food sources being seaweed.

From the newest fossil collection at the Heard Natural Science Museum and Wildlife Sanctuary.

Brittle Star

Brittle Star, Ophiura graysonensis [Del Rio Formation/Lake Waco Spillway/McLennan County, TX]

The class Ophiuroids is a large group of echinoderms which include the basket stars, Euryalida, and the more familiar brittle stars, Ophiurida. Although similar in appearance, they are not related to starfish which belong to the class Asteroidea. The brittle star has a central, disk-shaped body with long, flexible arms. In order to move, the brittle star wriggles its arms resulting in gliding movement reminiscent of snakes. As the common name implies, brittle stars are fragile, but can replace lost limbs. Although early members of Ophiuroids appeared during the Ordovician Period 500 million years ago, the still extant genus Ophiura is of the more recent Cretaceous Period 145 million years ago. Whole fossils of brittle stars are rare as they rapid fall to pieces after death due to their fragile nature.

From the newest fossil collection at the Heard Natural Science Museum and Wildlife Sanctuary.

Jimbacrinus

Crinoid, Jimbacrinus bostocki

Jimbacrinus, nicknamed feather star, belong to the order Cladida, long since extinct. These marine creatures were a type of crinoid, a class that is characterized by a fivefold symmetry and often confused for plants. While few crinoids exist in the present-day, they were once found found in larger numbers during the Paleozoic Era, particularly during the Permian Period. An abundance of fossils of Jimbacrinus are found in Western Australia where some species once grew up to 25 cm (10 in) tall. This specific genus lived solely in what is now Australia, but other fossils from the extinct family Calceolispongiidae have also been found in the United States and India in addition to Australia.

From the newest fossil collection at the Heard Natural Science Museum and Wildlife Sanctuary.

Trilobites

Trilobite, Asaphiscus wheeleri [Wheeler Shale/Middle Cambrian]

Trilobites are an extinct class of arthropods defined by distinctive three-lobed, three-segmented forms. Evidence of their existence dates back to the beginning of the Cambrian Period 542 million years ago. They dominated the seas until their extinction during the Great Dying, the most severe extinction event which occurred between the Triassic and Permian Period 251.4 million years ago. Fossils of these creatures have been found on every continent, with areas such as the Wheeler Shale in Utah, the Emu Bay Shale in Australia, the Burgess Shale in British Columbia, and the Chengjaing Formation in China as being notable locations to find trilobites. They ranged in size from 1 cm to 70 cm (28 in), had a flower-like eye, and a thick chitinous exoskeleton which was shed often. There are currently over 20,000 recognized species of trilobites organized into 10 different orders.

From the newest fossil collection at the Heard Natural Science Museum and Wildlife Sanctuary.

Ammonites

Pervinquieria trinodosa, Duck Creek, Bryan, Oklahoma

Ammonites are of the extinct marine invertebrates of the subclass Ammonoidea within the class Cephalopoda. The name ammonite arose in 79 AD from Pliny the Elder. It is derived from the Egyptian god Ammon and the symbolic rams horns in his depictions. As seen in all fossils, ammonites are recognized for their spiral shape shells although there is variation between species.

Ammonite, Unknown

These predatory creatures lived in a shell that were constantly built as they grew. The size varied with fossils of many found to be over 1 m (3 ft) in diameter. Their tentacles extended from the shell to snare prey. A sharp, beak-like jaw awaited in the middle of the tentacles. Although not closely related, they moved like modern-day nautilus. Chambers within the shell were full of either fluid or gas and allowed movement within the water column. They also had a method of jet propulsion through a funnel opening within the shell for more precise horizontal movement.

Unknown, Arcadia Park Shale, West Dallas, Texas

Ammonites first appeared and evolved during the Devonian Period of the Paleozoic Era 419.2 million years ago, and they existed until the end of the Cretaceous Period of the Mesozoic Era 66.0 million years ago, disappearing with the dinosaurs. Fossils of these creatures play an important role as size, shape, and shells of ammonites can be used to date geological layers. The septa, or dividing walls of the shell, can be used to classify order, and therefore time period, of the specimen.

From the newest fossil collection at the Heard Natural Science Museum and Wildlife Sanctuary.

Fossils

Fossil of a "bony fish" of the infraclass Teleostei

The word paleontology refers to the study of ancient life from the Greek words palaios (ancient) and logos (study). The word fossil comes from the Latin word fossilis (obtained by digging). Fossilisation occurs with the right circumstances: protection from scavengers and elements, and death in an optimal substrate such as sand, soil, mud, a river bed, or seabed. A sub-fossil is where decay, although slowed down, is still occurring and bone is still evident. A fossil is when chemicals and minerals percolate through the remains and recrystallizes it, or else erodes it leaving a hollow space. These remains that are dug up, from bones to teeth to skin, can be categorized by types. Trace fossils are evidence of animal behavior such as tracks, burrows, or coprolites. Mineralized fossils are when organic matter is replaced with minerals such as with bones, shells becoming pyrite or opal, or wood replaced with silica. An impression is when the creature decays but leaves an imprint in the sediment.

I was recently given a wonderful opportunity to photography, in detail, the newest fossil collection at the Heard Natural Science Museum and Wildlife Sanctuary. While the next number of post will be looking at some of these unique fossils, I will additionally be doing more detailed posts on Google+ if you'd like to see fossils that may or may not appear on this blog.

Brown Trout

Brown Trout, Salmo trutta

Brown trout are a non-native species first introduced in the United States in 1883 from Germany. These fish are relatives of Atlantic Salmon and popular with anglers which contributes to their purposeful stocking in a number of states. While brown trout have become well established in many areas, other place still periodically add more for the purpose of fishing. They are a very competitive species that often drive out natives. A brown trout will feed at night on other fish and invertebrates, and they can withstand environmental disturbances better than natives. A number of natives such as brook trout and Lahontan cutthroat have had severe population declines most likely due to brown trout populations.

Mimosa

Mimosa, Albizia julibrissin

Introduced from China, Mimosa, also called the Persian Silk Tree, can now be found throughout a large portion of the United States. The showy pink flowers which bloom from May to July make it a popular ornamental tree. Within Florida and Tennessee, it is considered an exotic pest plant. Although this plant tolerates moderate drought, most soil, and thrives in high summer heat, it is not winter hardy and much prefers watersheds. For these reasons, as well as other susceptibilities such as wilt and weak wood, mimosa has not become a highly invasive issue as of this moment. States where mimosa is becoming more an issue have encouraged alternatives to mimosa for planting such as redbud and flowering dogwood.

Gray Jay

Gray Jay, Perisoreus canadensis

The Gray Jay, although much more common in Canada and Alaska, can be found year round in patchy areas of the western United States. These birds have very thick plumage that envelopes the legs and feet when puffed, and feathers that cover its nostrils. They cache food during the summer to sustain through harsh winters. Their sticky saliva is used to glue small food items to branches above eventual snow lines. Gray jays have been observed making over 1,000 sticky caches within one day. This adaptation not only allows for survival during the winter far north, but makes late winter nesting possible.

Also known as Camp Robber, or Whiskey Jack.

Rather than attempt a second brood in the summer, they prepare for the winter and take advantage of all food sources possible. Omnivorous gray jays have been observed eating not only arthropods, berries, fungi, carrion, and eggs, but also baby bats and blood-filled ticks off other animals. These birds are well-known for their bold behavior, gaining nicknames such as "Camp Robber" and "Whiskey Jack" in their search for food.

Pygmy Nuthatch

Pygmy Nuthatch, Sitta pygmaea

The Pygmy Nuthatch is a songbird with preference for long-needled, open pine forests, especially older ponderosa pine forests. It is a small bird reaching only 9-11 cm (3.5-4.3 in), about a full 2 cm (1 in) smaller than other nuthatches. These birds are found year round in patchy ranges of the western North American continent. They eat insects and seeds, and will cache seeds all year, saving them by hammering the seed into crevices or under flakes of bark.

Unlike most other songbirds, the Pygmy Nuthatch breeds in large extended-family groups, and have nest helpers. These helpers, relatives and grown offspring, help defend the nest and feed the incubating females and chicks. Pygmy nuthatches do not roost alone, with one observation sighting 150 of these birds in a single roost hole. During the cold nights and after breeding season, these birds will huddle with other pygmy nuthatches in their tree cavity nest. The roost site changes to accommodate seasonal weather variations. A summer, breeding site generally has a larger entrance hole near branches, whereas a winter, non-breeding site will have a small hole, but larger space within to allow more birds inside.

Hummingbirds

♂ Broad-tailed Hummingbird, Selasphorus platycercus

Hummingbirds are known for their coloration which has earned them the nickname of flying jewels. Birds with colors such as red or yellow are due to pigmentation within the feathers. Those of blue are a result of selective scattering of light due to particles dispersed in the material of the feathers. Green coloration comes from a combination of pigmentation and light scattering, but iridescence, as seen in hummingbirds, comes from interference. As observed by Newton, thin film on the feathers of birds cause an interaction of light waves. This is why some species, such as the Broad-tailed Hummingbird, often look to have a black chin rather than the characteristic red expected depending on the viewing angle.

♀ Broad-tailed Hummingbird, Selasphorus platycercus

Hummingbirds are often associated with red flowers, but the associate of the two is not exclusive. The assumption that these birds prefer red has always been prevalent, but it does not hold up to experimentation. While a reasoning for a higher prevalence of red floral colors in hummingbird flora is seen, the reason has not been found. What has been discovered is hummingbirds visiting a vast variety of colored flowers, not just red flowers; however, there is a clear link between flower shape and hummingbirds. As expected with long bills, tubular flowers are properly associated with hummingbird. There has even been evidence of a link between sexual dimorphism in some hummingbird species and the flowers they visit. The bill differences in particular of male and female Purple-throated Carib Hummingbird of the Caribbean is a reversal of floral dimorphism of Heliconia plants, of which these birds are the sole pollinators. One species, Heliconia caribaea, is associated with the short, straight bills of males, while the species, Heliconia bihai, relates to the long, curved bills of females.

Hummingbird with a bird band on its leg.

The flying and hovering abilities of hummingbirds are well-known and studied. Although there are musculoskeletal differences between species within the family Trochilidae, the aerodynamic mechanisms hummingbirds employ are somewhat similar to those used by insects. As with other birds, the downstroke contributes the most to weight support, but upstroke plays an important role for hummingbirds in particular. The added creation of tip vortices from the wingbeats also helps to support the body weight of hummingbirds. While hovering is essential for hummingbirds, it proves an interesting issue with banding. Unlike most birds, if a hummingbird spots a mist net, it can stop midair before collision. A pull-string trap is often used to capture and band hummingbirds instead of mist nets. As expect, the bands themselves are incredibly small, varying in diameter to 0.3 mm up to 35 mm.