A watch is a small timepiece intended to be carried or worn by a person. It is designed to keep working despite the motions caused by the person’s activities. A wristwatch is designed to be worn on a wrist, attached by a watch strap or other type of bracelet. A pocket watch is designed for a person to carry in a pocket.
A weevil is a type of beetle from the Curculionoidea superfamily. They are usually small, less than 6 millimetres, and herbivorous. There are over 60,000 species in several families, mostly in the family Curculionidae.
Eyes are the organs of vision. They detect light and convert it into electro-chemical impulses in neurons. In higher organisms, the eye is a complex optical system which collects light from the surrounding environment, regulates its intensity through a diaphragm, focuses it through an adjustable assembly of lenses to form an image, converts this image into a set of electrical signals, and transmits these signals to the brain through complex neural pathways that connect the eye via the optic nerve to the visual cortex and other areas of the brain. Eyes with resolving power have come in ten fundamentally different forms, and 96% of animal species possess a complex optical system. Image-resolving eyes are present in molluscs, chordates and arthropods.
The crested gecko, New Caledonian crested gecko, Guichenot’s giant gecko or eyelash gecko, Correlophus ciliatus, is a species of gecko native to southern New Caledonia. This species was thought extinct until it was rediscovered in 1994. Along with several Rhacodactylus species, it is being considered for protected status by the Convention on the International Trade in Endangered Species of Wild Flora and Fauna. It is popular in the pet trade.
Mastodons are any species of extinct proboscideans in the genus Mammut, distantly related to elephants, that inhabited North and Central America during the late Miocene or late Pliocene up to their extinction at the end of the Pleistocene 10,000 to 11,000 years ago.
Slag is the glass-like by-product left over after a desired metal has been separated (i.e., smelted) from its raw ore. Slag is usually a mixture of metal oxides and silicon dioxide.
Caption by: Enchanted Learning
Sample provided by Max Barclay of the Natural History Museum in London and described by Stylianos Chatzimanolis of the University of Tennessee.
Darwinilus sedarisi is a species of rove beetle, the only species in the genus Darwinilus. It is named after Charles Darwin and David Sedaris. It is found in Argentina. A specimen of the beetle was collected by Charles Darwin in 1832 during the voyage of the HMS Beagle, but not formally named as a new species until 2014
Imaged at Entomology 2014 in Portland, OR.
The Nyholm lab studies beneficial host-microbe interactions between the Hawaiian bobtail squid, Euprymna scolopes, and the bioluminescent bacterium, Vibrio fischeri. Hawaiian bobtail squid are nocturnal predators, remaining buried under the sand during the day and coming out to hunt for shrimp at night neat coral reefs. The squid have a light organ on their underside that houses a colony of glowing bacteria (V. fischeri). The squid uses this bacterial bioluminescence in a form of camouflage called counter-illumination, masking it’s silhouette by matching moonlight and starlight; thus hiding from predators swimming below. The light organ is attached to the ink sac and it can use this ink like a type of shutter to control the amount of light. This likely helps the squid adjust to variable light conditions, for example cloudy nights or a full vs. new moon. In this image of a juvenile squid, you can clearly see the bi-lobed light organ and ink sac in the center of the squid’s mantle cavity.
The Hawaiian bobtail squid lay their eggs in clutches on the sea floor, where they take approximately three weeks to develop. This series of macropod images allows us to see the developing squid and monitor embryogenesis. Once the squid hatch, V. fischeri from seawater colonize the light organ within hours. This macropod image allows us to see a close-up view of the ciliated appendage-like structure found on the surface of the juvenile squid’s light organ. Once the squid hatches, the cilia assist in bringing V. fischeri in the seawater to pores at the base of the light organ. These pores lead to inner crypts, where only V. fischeri can enter and colonize. V. fischeri is a relatively rare member of the seawater bacterial community, making up less than 0.1%. The Nyholm lab is trying to understand how the squid’s immune system can differentiate between the symbiont and all the other different kinds of bacteria in seawater.
While the light organ of the squid exemplifies a highly specific beneficial relationship between bacteria and host to provide camouflage at night, this organ is only found in some squid species. All squid, however, are capable of another type of camouflage, cryptic coloration. Squid skin contains special pigmented cells called chromatophores that can change the overall color of the squid in seconds. Each chromatophore contains pigment granules surrounded by nerve and muscle fibers. When these muscles are contracted, the pigment sac expands, creating a larger surface area of color. When the muscles relax, the pigment sac can shrink to a small dot, 15 times smaller than their expanded size, hiding the color. In these macropod images you can see relaxed chromatophores on the mantle and contracted chromatophores around the eyes. The macropod images allow us to see these pigment cells in great detail.
