Lake McDonald is the largest Lake in Glacier National Park in Montana. It appears to be a pristine environment untouched by the hand of humanity. Unfortunately that appearance may only be skin deep. Scientific evidence indicates that whitefish and bull trout in the lake have levels of mercury that are higher than EPA limits for human or environmental health.

Differences in size, coloration, behavior and other characteristics between males and females of a species are termed sexual dimorphisms. There are many examples of species exhibiting sexual dimorphism, including humans, but one large species with extreme differences between the males and females is the northern elephant seal (Mirounga angustirostris).

Manzanita (Arctostaphylos spp.) is a member of the chaparral plant community that covers most of the mountain sides in southern California. Adapted to the hot, dry summers, and cool wet winters of California's Mediterranean climate, chaparral forms dense stands composed of numerous plant species.

The California Floristic Province is a biodiversity hotspot found along the Pacific coast of North America from northern Baja California to southwestern Oregon, and including most of California. Containing over 2100 species of unique plant species, over 70% of the habitat in this are has been lost to agriculture, urbanization, road construction and pollution. The California sycamore is a trees species native to the area.

Devil's Punchbowl is a Los Angeles County Park on the north side of the San Gabriel Mountains located near the town of Pearblossom, California. It is a canyon with steeply pitched sandstone walls formed by the combined action of erosion, and the movement of five or six fault zones. 

Since Copernicus put forth the revolutionary idea the sun, not the Earth was the center of the solar system, we have come to understand much more about our place in the universe. Rather than being at the center of it all, we exist on the outskirts of a rather average galaxy that is but one of between 100 billion and 200 billion galaxies in the observable universe.

Besides being enormous animals, the northern elephant seal (Mirounga angustirostris) also has enormous abilities when it comes to diving to great depths in search of food. In fact, among mammals the depths to which they can dive, and the time spent holding their breath is only exceeded by the sperm whale (Physeter microcephalus).

Blacksmith fish form large feeding aggregations above rocky reefs and kelp forests along the southern California coast. Specializing in feeding on tiny planktonic organisms, blacksmith have two adaptations that make them very successful at getting their prey.

A non-science blog this week. I wish everyone who reads this a season of peace and love. For those who celebrate Christmas - Merry Christmas.

Avalanche Creek in Glacier National Park flows through a beautiful gorge on its way from Avalanche Lake to McDonald Creek. Sperry Glacier, which feeds the lake and creek, was once one of the largest glaciers in the park. It has lost 75% of its area since the middle of the 19th century.

Sea hares, a kind of sea slug, will form large groups of individuals all involved in the process of reproduction. Each individual sea hare has both male and female reproductive systems, and each is capable for providing and receiving sperm simultaneously with other sea hares. The result is large masses of yellow eggs in strings that look like cooked spaghetti. 

Marine algae use the energy in sunlight to make food. The production of the soft blue light by the marine alga is the result of an interaction with sunlight that has nothing to do with photosynthesis. How is it produced?

Anacapa Island lies at the eastern end of the chain of islands forming the northern Channel Islands group. This chain of islands is an extension of the Santa Monica Mountains to the east. The east-west orientation of these mountains and islands is the result of massive tectonic forces twisting large chunks of the North American continental plate in a clockwise direction.

Sea hares are sea slugs that cruise the bottom looking for algae snacks. The California sea hare (Aplysia california) will excrete a purple ink when disturbed by a predator. Native Americans living near the coast used this ink to dye some of the materials they made.

Sea anemones are among my favorite underwater photography subjects. The beautiful colors and abstract forms captured in close-up compositions make for very interesting photos. Like all anemones, this white-spotted rose anemone (Urticina lofotensis) using stinging cells studding its graceful tentacles to capture passing prey.

The peaceful purple Swan Mountains lie beneath a forbidding layer of clouds moving or the Flathead Valley in northwestern Montana as the sun sets. This peaceful scene belies the tremendous forces and upheavals that were responsible for the creation of this landscape on the North American continent some 100 to 125 million years ago.

The North Fork of the Flathead River originates in British Columbia, Canada, and flows 153 miles (246 Km) south through Montana in the United States. It is one of only four rivers in Montana to bear the designation of Wild and Scenic. As it flows south from the Canadian border it forms the western boundary of Glacier National Park.

Bowman Lake is one of the large outflow lakes in Glacier National Park that provide evidence of the areas glacial past. While most of the glaciers are gone, the evidence of their erosional work clear stands out.

The Pulpit is a formation of Navajo Sandstone that stands in the Temple of Sinwava in Zion National Park. Like much of the geology of southwestern Utah, the Navajo Sandstone is the dominant rock type seen in Zion.

Like many tropical nudibranchs, Carlsonhoff's phyllidia (Phyllidia carlsonhoffi) has a striking color palette with a black velvety background, orange rhinophores, and yellow-capped bluish tubercles.