Notes Of A Dead Man Sequel (Notes - #3), Clive Cooper [free ebook novel .txt] 📗

"threatened species." One reason for the status is that manatees reproduce very slowly — the time between generations is about 20 years. In addition, fishermen trawling with nets in the Amazon and West Africa pose a grave threat to these slow-moving mammals. Also, in West Africa, manatees are hunted for their meat.

Habitat loss from waterfront development also impacts their survival. Manatees are also vulnerable to collisions with speedboats.

Other facts

Manatees are thought to have evolved from four-legged land mammals more than 60 million years ago. Except for the Amazonian manatee, their paddlelike flippers have vestigial toenails — a remnant of the claws they had when they lived on land. The Amazon species name "inunguis" is Latin for "without nails."

The name manatee comes from the Taíno (a pre-Columbian people of the Caribbean) word manatí, meaning "breast."

Manatees' eyes are small, but their eyesight is good. They have a special membrane that can be drawn across the eyeball for protection. Their hearing is good too, despite not having outer ear structures, because manatees have large inner ear bones.

Manatees' only teeth are called marching molars. Throughout a manatee's life, the molars are constantly replaced — an adaption to their diet of abrasive vegetation.

Manatees have only six neck vertebrae. Most other mammals, including giraffes, have seven. As a result, manatees cannot turn their heads sideways, and must turn their whole body around to look behind them.

Algae, photosynthetic organisms, often grow on manatees' skin.

Manatees never go on land.

Manatees don't always need to breathe. As they swim, they poke their nose up above the water's surface to catch a few breaths every few minutes. If they are simply resting, they can stay under the water for 15 minutes without taking a breath, according to National Geographic.

An animal that is similar to the manatee is the dugong (Dugong dugon). Dugongs are also in the order Sirenia, but they are in a different family, Dugongidae. These manatee cousins are found in the Indian and Pacific oceans. They have a notch in their tails, as well as tusks.

Manatees and dugongs may have inspired mermaid legends. In ancient mythology, sirens were monsters or sea nymphs who sang mesmerizing songs that lured sailors to steer their ships onto treacherous rocks. After a long sea voyage, sailors may have thought they were seeing sirens, or mermaids, when they were probably seeing manatees or dugongs.

Additional resources

The USGS Sirenia Project conducts long-term, detailed studies of the West Indian manatee. The Florida Manatee Program can tell you where to see manatees and provides a boater's guide to avoid collisions. At Save the Manatee Club, you can "adopt" a real manatee. Donations help fund manatee conservation." Cigarettes may raise risk of drug relapse

 by Lisa Chedekel-Boston U.

 

 

 

 

Continuing or initiating cigarette use after stopping the use of illicit drugs is linked to an increased likelihood of substance use relapse, research shows.

Past studies have shown that as many as three-quarters of adults with substance use disorders also have a history of cigarette smoking.

For the study in the Journal of Clinical Psychiatry, researchers, including Sandro Galea, dean of the School of Public Health of Boston University, examined the association between cigarette smoking and relapse rates among adults who had stopped illicit substance use.

They studied data from 34,653 adults enrolled in the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) who were assessed at two time points, three years apart, on substance use, substance use disorders, and related physical and mental disorders.

Daily smokers and non-daily smokers had about twice the odds of relapsing to drug use at the end of the three-year period compared to nonsmokers. Those odds held even after controlling for demographics and other factors, including mood, anxiety, alcohol use disorders, and nicotine dependence.

Specifically, among those with remitted substance use disorders who were smokers at the beginning of the study, more than 1 in 10 (11 percent) who continued smoking three years later relapsed to illicit substance use three years later, while only 8 percent of those who had quit smoking and 6.5 percent of never-smokers relapsed to substance use.

Among those who were nonsmokers, smoking three years later was associated with significantly greater odds of substance-use disorder relapse compared to those who remained nonsmokers.

“To our knowledge, no prior study has shown that cigarette smoking—both continued smoking and new-onset smoking—is associated with an increase in the likelihood of relapse to SUD among adults with past SUDs,” the authors say.

 

Exercise may help meth addicts avoid relapse

 

If further research confirms a relationship between smoking and relapse, then substance-use treatment programs should consider incorporating smoking prevention efforts into their services, the authors say. Only a minority of treatment centers report that they have formal smoking-cessation programs.

There are several possible reasons why smoking may increase the likelihood of relapse, the authors write, including that cigarettes may become a “cue” for use of illicit drugs, and that nicotine may cause increased cravings for stimulants and opiates.

While there have been some concerns that quitting smoking makes it more difficult to quit or stay off illicit drugs, cigarette abstinence “does not appear to lead to a compensatory increase in other drug use, and may even improve drug abstinence.”

Cigarette smoking is just one of many potential factors associated with SUD relapse, and more data are needed to determine the clinical significance of the association.

 

Psych patients want to quit smoking but don’t get help

 

But, they say, “The treatment of SUDs is extremely challenging, and even if not smoking is just modestly associated with improvements in sustained abstinence, this association may be useful in treatment programs.”

Additional coauthors are from Columbia University’s Mailman School of Public Health and the City University of New York.

 

Source: Boston University

Male glassfrogs could win ‘dad of the year’

 by Boston University

 

 

 

 

 

 

 

Glassfrogs lay their eggs on leaves hanging over streams in tropical rainforests, which makes them tasty snacks for snakes, insects, and other predators. When the survivors hatch, they drop into the streams to begin life as tadpoles.

Until recently, biologists thought the eggs of most species were on their own during this vulnerable stage, without any help from mom or dad. In just a few species, fathers were known to care for their developing embryos, and biologists thought this paternal devotion had evolved from ancestors entirely lacking parental care.

Walking along a stream in Panama very late one night, however, Jesse Delia, a PhD student in the lab of Boston University biology professor Karen Warkentin, spotted a glassfrog mother sitting on her clutch of eggs.

Working with research partner Laura Bravo Valencia, a graduate student at the Universidad de los Andes in Bogotá, Colombia, Delia went on to observe night-time parental behavior among no fewer than 40 species.

The two scientists discovered that in many species, glassfrog mothers brood their eggs during the night the eggs are fertilized, and that this care improves the survival of the eggs, while in almost a third of species, glassfrog fathers stay on guard for much longer periods.

Some frogs mate on land to avoid a ‘breeding frenzy’

Further, in an analysis of glassfrog evolutionary history that takes advantage of the new field data, the investigators discovered that male parental care probably evolved from female care. “Parental care gets elaborate when males take over,” Warkentin says.

These discoveries are based on “a tour de force of extreme fieldwork,” says Warkentin, senior author of the paper in the Journal of Evolutionary Biology. Delia and Bravo Valencia pursued their project over six rainy seasons at 22 sites along streams in Colombia, Ecuador, Mexico, Panama, and Peru. The project also included field monitoring of parental behavior throughout the duration of embryonic development for 13 species—a total of 18 months walking up and down streams every night.

Some of these streams were in warm lowland forests and others up in the Andes mountains. “In Colombia, we would take buses…into the mountains and try to find somebody who would put us up, somewhere close to a forest, a couple hours’ hike into the stream,” says Delia, corresponding author of the study. “Streams in the Andes are really steep, with impassable waterfalls every so often, and in many sites they are cascades of freezing cold water.”

In addition to observing the 40 species of frogs through the night, Delia and Bravo Valencia performed experiments on two species of frogs in Panama. The biologists began by removing glassfrog mothers immediately after the eggs were fertilized, before the mothers could sit on the eggs. Plucking out the frogs in this brief time period often required the researchers to jog up and down the stream, “so we were soaking wet all night,” Delia says.

Protective jelly

Monitoring the eggs daily until they hatched, which could take almost 20 days, showed that the eggs that received maternal care survived significantly better than those that did not.

Salty winter roads may mean fewer female frogs

The key to this survival was that the frogs were soaking up water from damp spots on leaves and delivering it to the eggs. The jelly surrounding the eggs then would swell up with water and grow about four times thicker. Offering these swollen egg packages to katydids, crickets that prey on frog eggs, frustrated the predators, Warkentin says.

“Each embryo is surrounded by this protective layer of jelly, so when the katydid bites, it’s getting mouthfuls of jelly, and it generally gives up.”

Basic fieldwork pays off

Bravo Valencia and Delia also tested what it would take to get glassfrog mothers to abandon their posts in the first few crucial hours. “They would gently poke and pinch and then physically push her off the eggs, and it would take all that to get most moms to leave,” Warkentin says. “The moms are extremely dedicated to their task in that time period.”

“…fathers not only took over the job…but they also greatly elaborated the amount of care.”

“These are relatively well-studied, charismatic frogs, yet we were fundamentally wrong about the reproductive behavior of most glassfrog species,” Warkentin notes. “There is still a lot to be learned from basic fieldwork. And that primary information has the potential to change how we think about larger processes, like sex-role evolution.

“In glassfrogs, maternal care helps embryos survive, but they seem to do the bare minimum,” she says. “It seems that fathers not only took over the job, when mothers were already doing it, but they also greatly elaborated the amount of care. Even after eggs have started hatching, fathers keep caring.”

“In many animals, mothers are on duty when offspring need intensive care, whereas fathers care when it’s easy or help out when more is needed. This common pattern has influenced how we think about parental sex-roles,” Delia says.

“Glassfrogs do the complete opposite—moms do the minimum (at least