When humans “domesticated” fire 400,000 years ago they made the right combination of conditions – longer periods with close human contact, plus smoke-damaged lungs – for tuberculosis to mutate from a harmless soil bacterium into our number one bacterial killer, according to new research.
These are coast redwoods (Sequoia sempervirens) in Humboldt Redwoods State Park, California. The park is home to the largest continuous block of old-growth redwood forest left on the planet- with some 10,000 acres.
The alluvial flats along its creeks and rivers are prime redwood habitats. The mix of rich soils, water, and fog rolling in from the ocean have produced the planet’s tallest forest. Of the 180 known redwoods greater than 350 feet, more than 130 grow here.
Coastal redwoods can be up to 379 feet (115.5 m) in height (without the roots) and up to 26 feet (7.9 m) in diameter at breast height.
Research now shows that the older such trees get, the more wood they put on- nice to see even trees go through a midlife spread.
Photograph by Michael Nichols, National Geographic
“The surface of a Cannabis sativa plant, showing glandular cells called trichomes that secrete a resin containing tetrahydrocannabinol (THC), the active component of cannabis when used as a drug.” Micrograph by Ted Kinsman for Wired Magazine.
If your memory doesn’t extend that far back (and I deny any statements by former students that I was there), don’t worry— DNA and RNA were on the spot.
So, back to 300 million years ago: reptiles evolved!! Not long after that (about 40 million years later), the reptilian evolutionary tree (called a clade) kept growing and other groups branched off. About 120 million years after the rise of the reptiles, one group, now called Lepidosauria, formed a new limb on the clade, thus separating themselves from the Therapsids, which eventually became mammals.
Jintasaurus is a hadrosauroid found in the Yujingzi Basin in the Xinminpu Group, Gansu Province, China. It dates back to about the Albian age of the Early Cretaceous, potentially sometime between 113 and 100 million years ago. It is known from the material of a single skeleton that includes parts of the skull, including the braincase. It had a long bone to which the lower jaw muscle would attach, allowing for a potentially unique system of chewing in this Hadrosauroid. Its discovery in Asia does, in addition, support an Asian origin for the Hadrosauroid group.
You, H. L., D. Q. Li. 2009. A new basal hadrosauriform dinosaur (Ornithischia: Iguanodontia) from the Early Cretaceous of northwestern China. Canadian Journal of Earth Sciences 46 (12): 949-957.
NOAA diver Dr. Steve Lonhart sizes up a hooded nudibranch in Monterey Bay National Marine Sanctuary. Also known as the lion’s mane nudibranch, the hooded nudibranch sweeps its raised hood through the water to catch food, then contracts it to force the food into its mouth. On this dive in 2011, researchers spotted a group of hooded nudibranchs with hoods exceeding 15 centimeters in diameter!
I feel like this is either sneaky or accidental foreshadowing of the press conference scene.
Judy’s eyebrows rise up in surprise yet not disbelief. To her this is very valuable, possibly true, information.
Nick’s eyebrows furrow as if offended, almost disgusted. He doesn’t know why the predators are going savage but he does believe without a doubt that it has NOTHING to do with biology.
This is one of the first if not THE first hint that the two would break up.
Jeyawati is a Hadrosauroid dinosaur known from the Moreno Hill Formation in New Mexico. It dates back to about 91 million years ago, in the Turonian age of the Late Cretaceous. It is known from fairly scattered remains of an adult individual from both the skull and the postcranial skeleton. It was found to be a fairly derived Hadrosauroid, helping to place the migration of the group from Asia to North America in a broader phylogenetic context. It had strangely long and sloping face that might indicate it had a different diet or feeding style than other Hadrosauroids. It may have had keratinous ornamentation on his head, allowing for visual display between members of the species.
McDonald, A. T., D. G. Wolfe, J. I. Kirkland. 2010. A new basal hadrosauroid (Dinosauria: Ornithopoda) from the Turonian of New Mexico. Journal of Vertebrate Paleontology 30(3): 799-812.
DARCY BÉHATI KEVERIAN PREMEDICAL PROGRAMME CLASS OF 2017
MEDICINE THE INTEGRATED BODY BODY SYSTEM TO CELLS
Each system can been seen as a hierarchy. The System itself is at the top of the hierarchy; next are its organs, then the tissues that make up the organs, and at the bottom this hierarchical tower are the cells from which tissues are made. A body system is usually regarded as a collection of organs and parts designed for one important task. The systems are integrated and interdependent, but each has its own identifiable components. The main parts of a system are its organs and tissues. The brain, for example, contains nervous, connective and epithelial (covering or lining) tissues. A tissue is a group of cells that are similar in structure and carry out the same function.
The World Health Organisation (WHO) is moving to declassify
transgender identity as a mental disorder, as it updates its category of
mental illnesses for the first time in decades.
The body, which is the public health agency of the United Nations
(UN), is considering making the change in a revised categorisation of
mental and behavioural disorders to be released in 2018.
News of the change comes just as a new study published in The Lancet Psychiatry this week advocates that transgender identity should not be diagnosed as a mental disorder.
“Stigma associated with both mental disorder and transgender identity
has contributed to the precarious legal status, human rights
violations, and barriers to appropriate care among transgender people,” says lead researcher Geoffrey Reed from the National Autonomous University of Mexico.
The New Mexico whiptail is a species of lizard with one extraordinary adaptation: every single one of them are female. In a complex process called parthenogenesis, females simulate the act of sex with one another, and lay eggs containing embryos that are exclusively female.