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In honor of Cinco de Mayo, we wish to shine our spotlight on the Mexican green rattlesnake (Crotalus basiliscus). Not much is known about this pit-viper species native to coastal western Mexico. The specific name is derived from the Greek word for king (basiliskos) and refers to this snake's large size and potent venom (chemically similar to that of the Mojave rattlesnake).

One of the largest rattlesnake species, the Mexican green rattler often exceeds 4.9 feet (150 cm) in length. Its body is moderately stout and rectangular in cross section. The Mexican green rattler is brown or grayish in color with diamond-shaped blotches with light edges. It's head is grayish-brown. The belly is white or cream-colored. The young are mostly red but adults eventually become an olive green. The Mexican green rattler is found in western coastal Mexico from southern Sonora to Michoacán. It's habitat is mostly tropical thorn forest. The Mexican green rattler is primarily active during the rainy summer months and most are found crossing the roads at night. Their primary prey is rodents. This species is classified as Least Concern on the IUCN Red List.

A rhinoceros (or "nose horn") is one of any five living species of odd-toed ungulates in the family Rhinocerotidae native to both Africa and Southern Asia. The rhinos are characterized by their large size, their herbivorous diet, their thick protective skin (formed of layers of collagen), their (relatively) small brains-for large mammals, and their characteristic large horns. While rhinos enjoy leafy plant material, they are able to digest more fibrous material in their hind-guts. The two African species - Ceratotherium simum (white rhinoceros) and Diceros bicornis (black rhinoceros) - lack front teeth and, instead, pluck leaves and grasses with their lips.

Rhinoceros horns are bought and sold on the "black market" where they are worth as much as gold (by weight). Rhino horns-which are made of keratin (the same protein that makes up your hair and fingernails) - are ground up and consumed in some cultures where people believe the horn-dust has healing and other therapeutic properties.

In honor of "Save the Rhino Day," we wish to shine the spotlight on the Sumatran rhinoceros. The Sumatran rhinoceros (Dicerorhinus sumatrensis) is the smallest rhinoceros species with mature adults standing just over four feet (1.3 m) high at the shoulder. Additionally, adult Sumatran rhinoceroses are generally between about seven feet and 10.5 feet (2.4-3.2 m) long and may weigh in at about 1,500 pounds (700 kg). The Sumatran rhinoceros is the most threatened rhinoceros species on the plant and that due mainly to habitat loss and illegal poaching. In fact, official conservative estimates numbered the Sumatran rhino at around 320-individuals in 1995. That number is probably closer to 220 in 2016 as the (comparatively) "pint sized" Sumatran rhino teeters on the precipice of extinction. Like its much larger African cousin, the Sumatran rhino has two horns. Uncharacteristically-for rhinoceroses anyway-the Sumatran variety has very dense hair (especially as young calves). Additionally, their color is reddish-brown, they have short, stubby legs, and their lips are prehensile. Historically this rhinoceros species was spread across South-east Asia. Today, however, they inhabit only small parts of Indonesia and Malaysia.

In honor of our newest symbol of these great United States of America, we would like to shine our spotlight on the American buffalo:

The American bison (Bison bison), also called the American buffalo, is a species of bovid that once roamed the grasslands of North America in massive herds. They became nearly extinct mainly due to commercial hunting and slaughter in the 19th century. The American bison has made a recent resurgence due largely to their inhabiting a few national parks and wildlife reserves. Historically the America bison enjoyed a range from the Great Bear Lake in Canada's far northwest, south to the Mexican states of Durango and Nuevo León, and east to the Atlantic Seaboard of the United States. In the eastern United States buffalo roamed from New York to Georgia (and perhaps as far south as Florida). [There are even reports of buffalo being seen in North Carolina as late as 1750.] American bison live in river valleys and on prairies and plains. Typical habitat is open grasslands, sagebrush, semiarid lands, and scrublands. Bison are largely grazers feeding primarily on grasses and sedges. Bison also drink water or consume snow on a daily basis.

The majority of American bison are raised for human consumption. The taste of bison meat is considered to be very similar to good beef. By contrast, however, bison meat is lower in fat and cholesterol and higher in protein than beef. In fact, it is for this very reason that ranchers have developed the "Beefalo." Beefalo is a fertile hybrid of bison and domestic cattle that confers the better qualities of bison meat to a more economical medium.

Female bison live in maternal herds which include other females and their offspring. Male offspring leave their maternal herd when around three years old and either live alone or join other males in bachelor herds. Male and female herds do not mingle until the breeding season (usually July through September). During the breeding season, dominant bulls maintain a small harem of females for mating. Male bison play no part in raising the young.

Finally, bison are among the most dangerous animals encountered by visitors to U.S. and Canadian national parks. While they appear slow (because of their "lethargic" movements), buffalo can easily outrun humans-bison can run as fast as 40-mph (64 km/h)-and they will attack humans if provoked. In fact, more injuries (and even deaths) of visitors to Yellowstone National Park have been attributed to bison than to bears.

In honor of national Save the Frogs Day, we would like to shine the spotlight on the bullfrog.

The American bullfrog (Lithobates catesbeianus) is member of the family Ranidae (e.g. “true frogs”;). The bullfrog has an olive green back, brownish-blotched sides, and a white underside spotted with yellow or grey. The bullfrog has a characteristic bright green upper lip and males have yellow throats.Bullfrogs inhabit the edges of large, permanent water bodies including swamps, ponds, and lakes. Males defend territories during the breeding season and his call is reminiscent of the roar of a bull (hence its common name). Bullfrogs are native to the southern and eastern parts of the United States and Canada. However, they have been introduced across other parts of North, Central, and South America, Western Europe, and parts of Asia. In fact, the bullfrog is harvested for use as food in many areas (including North America).

Bullfrogs are sexually dimorphic with males being smaller than females and having yellow throats. The tympanic membranes of males is larger than their eyes while the tympani of females are about the same size as the eyes. Bullfrogs measure about 3.6 to 6 in (9 to 15 cm) from snout to vent. They grow fast and large mature individuals can weigh more than a pound (500 grams). Further, some large bullfrogs have weighed in at as much as 1.8-pounds (800 grams) and have measured up to 8-inches (20 cm) in length.

Bullfrogs have a prolonged breeding season with males engaging continuosly while the receptivity of females is sporadic throughout the breeding season. The sex ratio is generally skewed toward males. These behaviors cause male-to-male competition to be high within the bullfrog population and sexual selection for females to be quite intensive.

A tapir is a relatively large, herbivorous mammal. Most tapirs are about 6.5 feet (2m) long and they stand about three feet (1m)high. Tapirs weigh between 350 and 700 pounds (150-300 kg). They are similar in shape to a pig and they have a distinctive short, prehensile snout. Tapirs inhabit jungle and forest regions of South America, Central America, and Southeastern Asia. Their closest relatives are other odd-toed ungulates including horses, donkeys, zebras, and rhinoceri. Their coats are short and range in color from reddish-brown to grey to nearly black. One notable exception is the Malayan tapir which has a white, saddle-shaped marking on its back. Tapirs have oval, white-tipped ears, stubby tails, and hooved-toes. Their four-toed front feet and three-toed hind feet help them to walk on muddy and soft ground. The striped and spotted coats of baby tapirs act as camouflage. Female tapirs have a single pair of mammary glands while male tapirs have characteristically long penises.

The tapir's snout is highly flexible allowing the animals to grab foliage that would otherwise be out of reach. Tapirs often exhibit the Flehmen response in which they raise their snouts and show their teeth to detect scents. Tapirs reach sexual maturity between three and five years of age. Female tapirs can reproduce every two years bearing a single calf after a gestation of about 13 months. The lifespan of a tapir is about 25 to 30 years. Apart from mothers and their young, tapirs lead solitary lives. A tapir's diet consists of fruit, berries, and leaves. Tapirs are predominantly nocturnal and spend most of their waking hours foraging for food.

Habitat loss has resulted in the watch-listing of all four tapir species: the Brazilian and Malayan tapirs are classified as vulnerable while the Baird's tapir and the mountain tapir are endangered.

Haplodiploidy is a sex-determination system in which males develop from unfertilized eggs and are haploid (n) and females develop from fertilized eggs and are diploid (2n). Haplodiploidy determines the sex in all members of the insect order Hymenoptera (bees, ants, and wasps).

The haplodiploid sex-determination system has a number of peculiarities. For example, a male has no father and cannot have sons (but he has a grandfather and can have grandsons). Additionally, recessive lethal and deleterious alleles will be removed from the population rapidly because they will automatically be expressed in the males. [In other words, dominant lethal and deleterious alleles are removed from the population every time they arise as they kill any individual in which they occur.]

Haplodiploidy is not the same thing as an XO sex-determination system. In Haplodiploidy, males receive one half of the chromosomes that females receive (including autosomes). In an XO sex-determination system, males and females receive an equal number of autosomes. However, when it comes to sex chromosomes, females receive two X-chromosomes while males receive only a single X-chromosome.

In honeybees, drones (males) are entirely derived from the queen (e.g. their mother). The diploid queen has 32-chromosomes and the haploid drones have 16-chromosomes. Drones produce sperm cells that contain their entire genome. Thus, the sperm are all genetically identical (except for mutations). The male bees' genetic makeup is therefore entirely derived from the queen while the genetic makeup of female worker bees is half derived from the queen and half from the father. If a queen bee mates with only one drone, any two of her daughters will share, on average, 75% of their genes. Finally, the diploid queen's genome is recombined for her daughters. However, the haploid father's genome is inherited by his daughters "as is." The natural world never ceases to amaze.

On this Earth Day, 2016, we would like to highlight The Great Pacific garbage patch. The "patch" is an area located in the central North Pacific Ocean and is characterized by exceptionally high relative concentrations of pelagic plastics, chemical sludge and other debris that have been trapped by the currents of the North Pacific Gyre. It consists primarily of microscopic particles suspended in the upper water column.

Environmental scientists believe that The Great Pacific garbage patch formed gradually as a result of anthropogenic pollution gathered by the ocean currents forming the North Pacific Gyre. The gyre's rotational pattern draws in waste material from across the North Pacific Ocean, including coastal waters off North America and Japan. As material is captured in the currents, wind-driven surface currents gradually move floating debris toward the center, trapping it there.

The Great Pacific garbage patch has one of the highest levels known of plastic particulate suspended in the upper water column. Unlike organic debris, which biodegrades, the photodegraded plastic disintegrates into ever smaller pieces while remaining a polymer. Thus the plastic becomes small enough to be ingested by aquatic organisms that reside near the ocean's surface thereby entering the food chain.

On the microscopic level, the floating debris can absorb organic pollutants from seawater. When ingested, some of these are mistaken by the endocrine system as estradiol, causing hormone disruption in the affected animal. These toxin-containing plastic pieces are also eaten by jellyfish, which are then eaten by larger fish. Some of these fish are then consumed by humans, resulting in their ingestion of toxic chemicals. Studies are currently underway to determine how best to deal with the Great Pacific garbage patch. And now you know.

First celebrated in 1970, Earth Day is an annual celebration during which events are held worldwide to demonstrate support for environmental protection. Earth Day is now coordinated globally by the Earth Day Network and is celebrated in more than 193 countries. Today, April 22, 2016, the landmark Paris Agreement was signed by the United States, China, and 120 other countries to satisfy a key requirement of the historic climate protection treaty adopted by consensus at the 2015 United Nations Climate Change Conference in Paris.

Happy Earth Day from all of us to all of you. #biologycoachonline #heybiologycoach

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