They are becoming old, sick, injured or are effected by melting ice and so have to seek food on land which is difficult when it is not nesting season. Also research is on going

From the article

There are 19 recognized polar bear subpopulations, but only two have been studied for long enough to show that changes in ice conditions are affecting the livelihood of some polar bears. Temperatures are rising in many regions of the world because high concentrations of greenhouse gases, such as carbon dioxide (CO2), are warming up the Earth's atmosphere. The effects are most notable in the colder regions of the world since a large portion of the ice cover comes from frozen ocean water, or sea ice. Sea ice forms at colder temperatures than freshwater ice, so when things warm up, sea ice is the first thing to melt.

Sea ice is the home of polar bears' major food source, ice seals, so when the sea ice disappears, so does the bears' main way of getting meals. Rising global temperatures are forcing bears to spend more time on land and to go longer between meals. "The climate can only continue to warm as[carbon dioxide] concentrations continue to rise," Amstrup said.

"There is a higher percentage of bears in this situation [starving] now because of sea ice retreat," Amstrup said. "We have documented the populations in Alaska and the western Hudson Bay of Canada. We have shown in both places that we have seen poorer survival rates."

Probably for the same reason when women ask for a man that his physically fit .

Kids May See Better If They Play Outside

by Agata Blaszczak-Boxe, Contributing Writer | September 15, 2015 01:34pm ET



Children who spend more time outdoors may have a lower risk of becoming nearsighted, new research suggests.

In the study, researchers looked at about 1,900 schoolchildren in China. The scientists found that the kids who had been instructed to spend more time outdoors over three years were 23 percent less likely to develop nearsightedness during this time than those who had not been instructed to spend more time outdoors.

Moreover, among the kids who did become nearsighted during the study, the degree to which their eyesight worsened was slightly smaller among those who spent more time outdoors, the researchers found.


Although the study was conducted in China, the results likely apply to children elsewhere, too, said study author Dr. Mingguang He, of the Zhongshan Ophthalmic Center, in Guangzhou. Previous research has suggested "the protective effect of outdoor time in Australia and United States on children of European ancestry," he said.

In the study, the researchers selected six schools and assigned the children, whose average age was 7 at the study's start, to attend one additional 40-minute class of outdoor activities during each school day for three years. The parents of these children were also encouraged to engage their children in outdoor activities after school, especially during weekends and holidays. The other half of the children, from another six schools, continued their usual activity patterns. [10 Scientific Tips for Raising Happy Kids]

After three years, 30.4 percent of the kids in the intervention group had become nearsighted, compared with 38.5 percent of the kids in the control group, the researchers found.

The reduction in the risk of nearsightedness found in the study is important, because children who develop nearsightedness at a young age are most likely to develop worse myopia (the medical term for nearsightedness) later on, the researchers said. This means these children are at increased risk of "pathological myopia," which is a severe form of vision impairment.

"Thus, a delay in the onset of myopia in young children, who tend to have a higher rate of progression, could provide disproportionate long-term eye-health benefit," the researchers wrote in their study, published today (Sep. 15) in the journal JAMA.

It is not clear exactly why spending more time outside would benefit children's eyesight, the researchers said. However, some research has suggested that the higher levels of light intensity found outdoors may increase the release of the chemical dopamine from the retina of the eye, He said. In turn, dopamine is known to inhibit the type of growth in the eye that is associated with myopia, he said.

Based on the new results, the researchers recommend that children spend more time outdoors because of the potential benefits to their eyesight, He said. "In fact, in order to maximize the benefit, we should further increase the outdoor time by using school recesses and encouraging parents bring their children outside on weekends, He said.

However, it's important to protect kids' skin and eyes from UV light, which can be damaging, he noted. The American Academy of Pediatrics recommends that children stay in shaded areas when possible, wear a hat or cap, and use broad-spectrum sunscreen.

"Given the popular appeal of increased outdoor activities to improve the health of school-aged children in general, the potential benefit of slowing myopia development and progression by those same activities is difficult to ignore," Dr. Michael X. Repka, a pediatric ophthalmologist at the Johns Hopkins University School of Medicine, Baltimore, who was not involved in the study, wrote in an editorial accompanying the study in the journal.

But parents should understand that any benefit to children's eyesight of spending more time outside "is likely to be small," and it is uncertain how long this benefit may last, Repka wrote.

Follow Agata Blaszczak-Boxe on Twitter. Follow Live Science @livescience, Facebook & Google+. Originally published on Live Science

Starving Polar Bear Photo: Don't Blame (Just) Climate Change

by Elizabeth Newbern, Staff Writer | September 15, 2015 04:12pm ET




Polar bears have become the fuzzy face of the impacts of climate change, with shrinking sea ice in the Arctic affecting how the bears normally roam and hunt. Now, after a photograph of an emaciated polar bear hobbling on ice went viral online, some people are wondering if global warming is causing these majestic creatures to starve.

Wildlife photographer Kerstin Langenberger snapped the now-famous photo of the gaunt polar bear and wrote a concerned Facebook post questioning the health of polar bear populations. Though it was widely circulated online, the photograph is misleading, said Karyn Rode, a wildlife biologist at the U.S. Geological Survey in Anchorage, Alaska.

"I think you are always going to have animals in any population [that are] in poor conditions," Rode said. This can be because they have an injury (as may be the case with the polar bear in the photo) or because the animal is old and has lost some of its canines, she said.

Steven Amstrup, chief scientist at Polar Bears International, a nonprofit research organization dedicated to studying polar bears, agreed and added that seeing a skinny bear in the wild is not altogether uncommon. "We know that animals in the wild don't live forever," he said. "Polar bears, they don't have natural enemies, so when they die it's of starvation."

There are 19 recognized polar bear subpopulations, but only two have been studied for long enough to show that changes in ice conditions are affecting the livelihood of some polar bears. Temperatures are rising in many regions of the world because high concentrations of greenhouse gases, such as carbon dioxide (CO2), are warming up the Earth's atmosphere. The effects are most notable in the colder regions of the world since a large portion of the ice cover comes from frozen ocean water, or sea ice. Sea ice forms at colder temperatures than freshwater ice, so when things warm up, sea ice is the first thing to melt.

Sea ice is the home of polar bears' major food source, ice seals, so when the sea ice disappears, so does the bears' main way of getting meals. Rising global temperatures are forcing bears to spend more time on land and to go longer between meals. "The climate can only continue to warm as[carbon dioxide] concentrations continue to rise," Amstrup said.

"There is a higher percentage of bears in this situation [starving] now because of sea ice retreat," Amstrup said. "We have documented the populations in Alaska and the western Hudson Bay of Canada. We have shown in both places that we have seen poorer survival rates."

Also, there are several polar bear populations that aren't very well studied, so it's impossible to say that polar bears are generally struggling because of climate change, Rode said. "There has been no study that I know of that said more bears starve specifically as a result of climate change," she added. "There have been models of that, but there has been no empirical data to support that."

Shrinking sea ice is causing polar bears to starve with higher frequency, but "[y]ou can't say that any one individual is starving because of climate change," Amstrup said.

As the climate warms and sea ice continues to decline, the frequency of starving bears is only going to rise — not because of climate change directly, but because the loss of sea ice is taking away their main food source, Amstrup added.

Some scientists have speculated that there is a chance polar bears may find alternative food sources on land, but a study published in April in the journal Frontiers in Ecology and the Environment by Rode, Amstrup and others found that the bears' food prospects on land aren't great.

While there are some viable nutrient sources available on land, such as bird eggs these aren't present in the amounts that can sustain polar bear populations year round, Rode explained. Bird eggs are only available during the spring, when birds are breeding, so searching for food on land in other season won't meet polar bears' nutritional needs as easily. Which leaves the bears in a bit of a quandary, unless they can travel northward with sea ice retreat or find ways to hunt bigger game than bird eggs.

Thank you

This part of the article was kind of funny

Every galaxy of note seems to have a supermassive black hole, weighing millions or billions of times as much as the sun, burping sparks of half-eaten stars and gas.

The article did mention that 10 second bursts does cause ozone damage . I am also reading about Supper Massive black holes from the article ...neat



Integral has seen about 100 of the brightest supermassive black holes, the main producers of gamma radiation in our universe, in other galaxies. But while looking for them in nearby galaxies, surprisingly few have been found. They are either too well-hidden or are only present in the younger galaxies which populate the more distant universe.

When do you think the next ice age will be ? What are your thoughts on holes in the ozone ?

Global warming isn't helping either water levels are rising .

http://ecowatch.com/2015/05/22/maldives-underwater-climate-change/

It’s not just low-lying island nations either. “A recent study says we can expect the oceans to rise between 2.5 and 6.5 feet (0.8 and 2 meters) by 2100, enough to swamp many of the cities along the U.S. East Coast,” says National Geographic. “More dire estimates, including a complete meltdown of the Greenland ice sheet, push sea level rise to 23 feet (7 meters), enough to submerge London.”



http://qz.com/193139/the-biggest-tsunami-recorded-was-1720-feet-tall-and-chances-are-good-it-will-happen-again/

They come taller than that, though. The 1958 tsunami that ripped through Lituya Bay, a sleepy fjord near the Gulf of Alaska, was eight times bigger. And though its causes make it different from the far-traveling waves that slammed Southeast Asia in 2004 or Japan in 2011, the warming of the atmosphere will make both types become more common.

It passes the time .

Interesting read. I managed to find this information.



The biggest tsunami recorded was 1,720 feet tall and chances are good it will happen again


http://qz.com/193139/the-biggest-tsunami-recorded-was-1720-feet-tall-and-chances-are-good-it-will-happen-again/

http://www.livescience.com/13176-history-biggest-tsunamis-earthquakes.html

Written by
Gwynn Guilford

Obsession
The Sea
March 30, 2014



Fifty years ago this week, the Great Alaska Earthquake ravaged the Pacific Northwest, killing more than 100 people. Nine-tenths of those weren’t caused by the earthquake, though, but by a series of tsunamis that pummeled the coast, one of which towered 219 feet (66 meters) high.






They come taller than that, though. The 1958 tsunami that ripped through Lituya Bay, a sleepy fjord near the Gulf of Alaska, was eight times bigger. And though its causes make it different from the far-traveling waves that slammed Southeast Asia in 2004 or Japan in 2011, the warming of the atmosphere will make both types become more common.





​
Calamity struck at 10pm on July 9, 1958, when a 8.0-Richter-scale earthquake rammed the Alaskan coast up and northward. That impact shook free between 40 million and 60 million cubic yards (30.6 million and 46 million cubic meters) of rock and ice that rimmed the Lituya basin, dumping it 3,000 feet into the bay below. The 1,720-foot monster that reared up as a result shot through the bay at 100 miles per hour (161 kilometers per hour), as Susan Casey details in her book, The Wave: In Pursuit of the Rogues, Freaks and Giants of the Ocean.


Amazingly, four people survived. They were split between one boat that powered directly up the face of the still-building wave, and another that rode it like a surfer about 80 feet above the treetops, until being dumped into the Gulf of Alaska in a hail of uprooted trees.





The 1958 megatsunami scoured Lituya Bay’s mountains bare.(DJ Miller, US Geological Services)
Flanked by ledges of ice and rock—and close to a fault lively enough to dislodge them and cause avalanches—Lituya Bay’s topography is uniquely lethal. Geologists say that a 492-foot wave hit (paywall; pdf, p.155) in 1936, and a 394-footer in 1853. French and Russian explorers met nasty ends there, according to Casey (one christened the middle island “Cenotaph,” which means a monument to the dead.) And then there’s the story Casey retells of a Tlingit Indian woman who returned from a day of berry-picking to find her entire village swept away, the corpses of her clan strewn among the remaining trees.






Most tsunamis in historical record start differently, though. Volcanic rumblings and shifting tectonic plates cause undersea earthquakes. When those quakes force enough land upward, they displace huge ripples of water that grow into tsunamis. The Ring of Fire—the volcanic ridge that curls around the Pacific Ocean—is the planet’s most seismically active, generating 80% of the world’s earthquakes—which is why so many tsunamis slam into Japan and Chile. Landslides, both underwater and above, can create huge waves like Lituya’s; earthquakes are usually, though not always, responsible.





A map of earthquakes and tsunamis from recent history (tsunamis in yellow).(Woods Hole Oceanographic Institute)
A warming climate ups the chance of both types. Melting glaciers redistribute weight across the planet and the related pressure bends the sea floor, increasing volcanic activity.






In fact, that’s what happened at the end of the last ice age, as Casey explains. Though it’s impossible to know exactly how that changed the seas, scientists have some clues—for instance, the undersea landslide off Norway about 7,900 years ago. The resulting tsunamis were only 32-64 feet (pdf). Still, those waves swallowed up a big enough chunk of the coast of the Netherlands, Germany, and Denmark that they helped turn Britain into an island.

There was something awesome in the thought of the solitary mortal standing by the open window and summoning in from the gloom outside the spirits of the nether world.

- Sir Arthur Conan Doyle


Copyright 2005 Dr. Dorothy McCoy

Article Source: Ezine Articles

Added January, 2006



Dr. Dorothy McCoyAbout the Author: Dr. McCoy is a psychotherapist, writer and police consultant. Her published books are: From Shyness to Social Butterfly, The Ultimate Book of Personality Tests (the article is from this book), and The Manipulative Man. She resides in Boone, North Carolina with her Great Dane, Sophie.









Do you have a unique awareness that is completely unrelated to your five senses? Do you sometimes know things, yet you cannot explain how you know them? It is said that some individuals are so exceptionally sensitive to their environment, they can perceive what most cannot-- disembodied spirits. Perhaps, you are one of these "exceptional” people. All cultures have legends, told in hushed voices, as the tellers look fearfully around. They speak of spirits who cling tenaciously to this world. They are no longer of this earth, yet they remain among the living; sadly unaware they are dead. In the "scare you to death” movie, the Sixth Sense, this was the explanation given for ghostly visitations. According to the movie, a few "gifted” individuals are capable of perceiving these ostensibly unwelcome spirits. Unfortunately, since I missed the first few minutes of the movie, Bruce’s lack of respiration came as a heart stopping revelation to me, just as it did to poor, wretched, dead Bruce Willis. Oops, sorry, I forgot, his heart had already stopped. Are you a ghost magnet such as the mendacious, beleaguered semi-heroine of Ghost, Whoopi Goldberg?



Are spirits powerless to move on because of a thirst for revenge, a desire to protect the living, or, perhaps, because of a horribly brutal death? We have no definitive answers for these questions. Sane, responsible individuals have reported encountering these displaced spirits. Eleanor Mondale (daughter of the former vice-president) insists a ghost visited her one night at the vice-president’s house (Evans & Huyghe, 2000). It is said, that Presidents Abraham Lincoln and James Garfield did not "leave the building” when their terms expired. They are still there, alarming unsuspecting guests. Why do some visitors see the illustrious former presidents and others do not? Are you one of the special people who could see Honest Abe or feel his ghostly presence? Let’s take the test and see. Hush. Wait. Did you hear that noise?



The "Can You See Ghosts” Test

1. Have you ever known the phone was going to ring before it rang?

Yes___ No___

2. Have you ever felt a sudden chill in a room, when there was no apparent reason?

Yes___ No___


3. Have you ever seen anything that could not be explained by science and logic?

Yes___ No___

4. Have you ever felt you were being watched when you were alone?

Yes___ No___

5. Have you ever had a vision or a dream that came true?

Yes___ No___

6. Have you ever had a successful session with a Ouija Board?

Yes___ No___

7. Do you have an open mind about the supernatural?

Yes___ No___

8. Would you refuse to spend the night in a "haunted” house?

Yes___ No___

9. Do you meditate?

Yes___ No___

10. Have you retained the childlike ability, simply to "accept” new experiences without distorting preconceptions?

Yes___ No___

11. Are you more likely to make decisions using your "gut feeling” than your "thinking logic?”

Yes___ No___

12. Have you ever been told that psychic ability runs in your family?

Yes___ No___

13. Do you wear black 90% (or more) of the time?

Yes___ No___

Scoring your test:

Give yourself one point for each "yes” answer. As for question "13,” I was just kidding. I wear black much of the time…but then, now that I think about it, there was that time I was alone in my 100 year-old farmhouse, and I heard… Perhaps, I will share that in the next book.

Understanding your Score:

Scores 1 – 4

Your psychic ability has not been fully developed. Perhaps, your personality is rational and pragmatic and you prefer to see "phenomena” that can be explained by logic. However, if you are interested in improving you psychic ability you can practice meditation and open yourself up to new experiences. There are on-line sites that offer information about and guidance in the fascinating world of the supernatural, which has a virtual Ouija Board. Werner Heisenberg (Physics and Philosophy: The Revolution in Modern Science) wrote, "… many new elementary particles may be created from the available energy and the old particles may have disappeared…” In other words, something dies and something new is created from its residual energy. Makes sense to me. Is this a possible explanation for the presence of ghosts…if, indeed, they exist? See, logic and reason…

Scores 5 – 8

You are coming along quite nicely. Your score indicates that you are open to unique experiences and you esteem an open, inquisitive mind. You may have experienced the supernatural. Perhaps, you would like to enhance this area of your personality by learning more about spirits. Here are several fascinating sites:

http://www.rockymountainparanormal.com/

http://www.torontoghosts.org/

http://www.sgvpr.org/

Scores 9 – 12

It is certainly possible that you have psychic ability. Your score is very encouraging. You, as well as the last group, may have experienced the supernatural. It would be a pity if you did not learn more about this enthralling subject and about your innate ability. Look at the sites listed and perhaps take a ghost tour, plan a vacation to spots that are rumored to be haunted and read some scholarly books on the paranormal. Good ghost hunting!

Our Guest Experts

Dr. David Oester, of the International Ghost Hunters Society was kind enough to provide this information (personal e-mail) on key character traits for a ghost hunter.

"It has been our experience over the last combined 28 years of ghost research that the people who have experiences with ghosts are those with an open mind and those with a closed mind, as in total skeptic, fail to have any experiences. It is okay to be skeptical, but a skeptic's mind is closed to anything paranormal. An open mind is the only characteristic that we have discovered. We had have over 4 million visitors to our site and all of them with experiences if married, and their spouse is closed minded will not have any experiences with the paranormal. This open mindedness spans race, color, creed or sexual orientation and equally so, those that are closed minded are closed to any kind of paranormal experiences.”

Wendy Haver, a Spiritual Counselor, from Rocky Mountain Paranormal Research Society, was kind enough to provide more insight (personal e-mail) into the personality of ghost hunters.

"Many seem to be more open to having such experiences occur. Not that they believe in ghosts necessarily, but will admit to it being a possibility.

Education level does not seem to be a factor, but intelligence might be. Those of an average or slightly less than average intelligence seem not to report as much activity as those of a higher intelligence or those of a significantly altered intelligence such as mental retardation (higher functioning so as to be able to report events)

Age may not be a factor but the environment in which they were raised does seem to factor. This has changed over time and so it will skew any age related reports.

One must take into consideration those who have had experiences vs. those who are willing to report their experiences. There are many who will not openly admit to such things. Therefore, you could say that being willing to talk about this sets them apart.”



When you have eliminated all which is impossible, then whatever remains, however

improbable, must be the truth. …Sir Arthur Conan Doyle

Ancient Human-Size Fish Breathed with Lungs

by Laura Geggel, Staff Writer | September 15, 2015 03:16pm ET


Before the dinosaur age, the coelacanth — a hefty, mysterious fish that now breathes with its gills — sported a well-developed lung, a new study finds.

This lung likely helped the fish survive in low-oxygen, shallow waters hundreds of millions of years ago, the researchers said. During the Mesozoic era, more commonly known as the dinosaur age, it's likely that some species of coelacanth (see-leh-kanth) moved to deeper waters, stopped using their lungs and began relying exclusively on their gills to breathe, the researchers said.

This adaptation to deep water likely helped coelacanths survive the asteroid that slammed into ancient Earth and killed the nonavian dinosaurs, the researchers said. The fish's gill- and lung-breathing relatives were not as lucky; during the Late Cretaceous period, about 66 million years ago, coelacanths living in shallow waters disappear from the fossil record, they said.


The hulking 6.5-foot-long (2 meters) fish has long baffled scientists. Fossils of the predatory fish date back to the early Devonian period, about 410 million years ago. The fish was thought to have gone extinct after the dinosaur-killing asteroid hit Earth, but living coelacanths were discovered off the coast of South Africa in 1938.

Today, there are two known species of living coelacanths that live in the deep waters near Mozambique and Indonesia. Scientists have collected and preserved entire specimens of these fish (which give birth to live young) over the decades, allowing researchers to study how the fish change from embryos to adulthood.



In the new study, researchers examined the curious lungs of one species of coelacanth (Latimeria chalumnae) at five different stages of growth. They scanned each specimen with X-ray tomography, a method that allows researchers to take multiple X-rays of an object, compile them and create a 3D image.

"Our results demonstrate the presence of a potentially functional, well-developed lung in the earliest known coelacanth embryo," the researchers wrote in the study. However, as the embryo grows, its lung development slows, and it eventually becomes a vestigial (functionless) organ in the fish, they observed.

Interestingly, adult L. chalumnae have small, hard, flexible plates scattered around their vestigial lungs. It's possible that these plates are similar to the "calcified lung" of fossil coelacanths, said Paulo Brito, one of the study's researchers and a professor of zoology at Rio de Janeiro State University in Brazil.

"In fossil coelacanths, these plates surrounding the lung most probably had a function in lung volume regulation, moving over each other to accommodate volumetric changes," Brito told Live Science in an email. "In extant [living] coelacanths, it represents a rudimentary anatomical structure."

It's possible that the lung became less developed as the coelacanth moved to deeper waters, but remnants of it still exist as a vestigial organ, the researchers said. However, as the lung shrank and became useless, a fatty organ that the fish uses for buoyancy control in deep waters grew and took over the space once occupied by the lung.

"Although we cannot know whether the fatty organ ever existed in fossil forms, due to its unique soft-tissue constitution, this organ in Latimeria has a function in buoyancy control," the researchers said in the study.

Given that the coelacanth has evidence of "calcified lungs" in the fossil record, as well as a developing lung early in its embryonic development, it's possible that the "lung is a primitive character[istic] in bony fishes," Brito said. Lungs are also present in most ancient ray-finned fishes (a subclass of boney fishes), lungfishes and living lobe-finned fish (such as the coelacanth), as well as four-legged vertebrates, including amphibians, reptiles, mammals and birds.

The new findings were published online today (Sept. 15) in the journal Nature Communications.

Latest News - September 15, 2015


http://www.righttoplay.com/moreinfo/newsevents/Pages/newsitem.aspx?articleID=74


Chelsea Clinton'��s new book



cover-itsyourworld.jpgWe are excited to announce that a story about our work with girls in Pakistan has been included in our friend Chelsea Clinton's new book, It's Your World: Get Informed, Get Inspired & Get Going. Chelsea's book is released today, in book stores and online, and includes stories and information that will inspire people to get involved and make a difference in the world.

As Vice Chair of the Bill, Hillary and Chelsea Clinton Foundation, she helps lead the work of the Foundation across its various initiatives, with a particular focus on work related to health, women and girls, creating service opportunities, and empowering the next generation of leaders.

You can learn more about Chelsea and the book at ​www.itsyourworld.com.

http://igg.me/at/themessengerdoc/x

THE MESSENGER DOCUMENTARY SNEAK PREVIEW! At the Max Planck Institute for Ornithology in Germany, Martin Wikelski introduces the ultimate bird banding project ICARUS – International Cooperation for Animal Research Using Space. Find out more: TheMessengerDoc.com

Well that is one very infested cat :(

Agreed.

Yes that is a possibility Or ....


Types of Fleas

Posted on August 1, 2013 by author


http://fleabites101.com/types-of-fleas/

Oriental Rat Fleas (Xenopsylla cheopis)

The Oriental rat flea feeds on rodents and is also referred to as the tropical rat flea. They are incredibly dangerous in that they can be carriers of bubonic plague and murine typhus. Though each of the preceding fleas carry diseases of their own, the Oriental rat flea is far more deadly. This is the flea believed to be responsible for spreading the plague throughout Europe and may have resulted in nearly 200 million deaths.

The Oriental rat flea tends to be a smidge larger reaching sized of 2.5 millimeters and Wikipedia states:

The Oriental rat flea has no genal or pronotal combs. This characteristic can be used to differentiate the oriental rat flea from the cat flea, dog flea and other fleas




Types of Fleas

Posted on August 1, 2013 by author


There are believed to be well over 2,000 different types of fleas throughout the world. The most common of these wingless parasites are the following:
•Cat fleas
•Dog fleas
•Human fleas
•Oriental rat fleas

You might be shocked to read that there is such a thing as “human fleas” because we most often think of fleas in the context of living on cats and dogs and jumping on to humans to feed whenever the opportunity arises. But, yes, there are human fleas and we will get to that in a minute.

What Do Fleas Look Like?

With there being so many different types of fleas please understand that though we will give a general description below that there are variances in many of these characteristics.

Fleas do not have wings and are thus unable to fly around. Instead, they move primarily by jumping with powerful legs. They can jump approximately 8 inches which is more than 150 times their height and would be the equivalent of the average human being jumping nearly 1,000 feet into the air. They also move with the assistance of their hosts (animals or humans) transporting them from place to place. Fleas are very dangerous when it comes to the spreading of diseases because they hitch rides on the fur of their hosts like humans ride airplanes and they can therefore infect vast expanses of lands as was the case with the Bubonic Plague that ravaged Europe.



Their bodies are usually squished like a vertical pancake making it very easy for them to weave in and around the hair follicles on animals. They also possess backward facing hairs and barbs on their little bodies that allow them to keep their grasp on animals even when they attempt to scratch themselves to remove the pests. They generally tend to be reddish-brown in color and possess very strong exoskeletons that make it difficult for them to be squished or killed. When a human being tries to crush a flea between their fingers, the flea often jumps away unscathed.

Cat Fleas (Ctenocephalides felis)

The cat flea may very well be the world’s most populous flea and responsible for most of the “flea damage” the human race incurs. It doesn’t take a rocket scientist to figure out that the primary host for cat fleas are domesticated cats. However, the cat flea can live on a wide variety of hosts, including dogs. Some have stated that you are actually more likely to find a cat flea on a dog than an actual dog flea. They are also apt to bite humans.

Cat fleas are about 2 millimeters in length when full grown and have a four-stage lifecycle. Adult fleas lay wet eggs that attach themselves to the skin and hair of the host. As they dry, the eggs will generally drop off into the bedding/resting area of the host. The eggs hatch into larvae and feed on organic material (dried blood and adult flea feces which contain blood) in the area where they hatch. As juvenile growth hormone in flea larvae decreases they morph into flea pupae and the enter adulthood and reproduce all over again.

Dog Fleas (Ctenocephalides canis)

The dog flea may be the Rodney Dangerfield of fleas with the cat flea greedily bogarting canines, too. Dog fleas are fairly rare in America and are more often found in Europe. And the anatomical differences are generally only identifiable under a microscope. Wikipedia states:

The dog flea can be distinguished from the very similar cat flea by its head, which is anteriorly rounded rather than elongate, and the tibiae of its hind legs, which exhibit eight setae-bearing notches rather than six.

So, though there are intrinsic differences between the cat and dog flea, you will be hard-pressed to see them and for all practical matter there is very little difference in how they impact the health and well-being of humans and animals. With that said, they do carry and transmit some different diseases.

Human Fleas (Pulex irritans)

Believe it or not, there are human fleas. Thankfully, due to proper hygiene and improved sanitation efforts in America, the presence of human fleas on actual humans is incredibly rare. In fact, you are far more likely to find them on domesticated pigs.

A website devoted to discussing fleas and their interactions with humans states:

Adult Pulex irritans are reddish-brown and the largest females can be one and half times the size of the smaller males. Also, the abdomen and thorax of the human flea are larger than the head which is much smaller in proportion to its overall body size.

Believe it or not, guinea pigs may have been the original host for human fleas as it is believed that they originally hail from South America.

Oriental Rat Fleas (Xenopsylla cheopis)

The Oriental rat flea feeds on rodents and is also referred to as the tropical rat flea. They are incredibly dangerous in that they can be carriers of bubonic plague and murine typhus. Though each of the preceding fleas carry diseases of their own, the Oriental rat flea is far more deadly. This is the flea believed to be responsible for spreading the plague throughout Europe and may have resulted in nearly 200 million deaths.

The Oriental rat flea tends to be a smidge larger reaching sized of 2.5 millimeters and Wikipedia states:

The Oriental rat flea has no genal or pronotal combs. This characteristic can be used to differentiate the oriental rat flea from the cat flea, dog flea and other fleas

I think that you may miss your home too much. lol

http://www.cdc.gov/plague/faq/#vaccine

Is a vaccine available to prevent plague?

A plague vaccine is not available. New plague vaccines are in development but are not expected to be commercially available in the immediate future.




Page last reviewed: June 13, 2012
Page last updated: June 16, 2015
Content source: Centers for Disease Control and Prevention
National Center for Emerging and Zoonotic Infectious Diseases (NCEZID)
Division of Vector-Borne Diseases (DVBD)

This is true both bacteria and viruses can be helped by vaccines. Perhaps the plague is not so much as a concern to worry about developing a vaccine yet?


http://www.health24.com/Medical/Cholera/Cholera-vaccination/Vaccines-against-bacterial-diseases-20120721

http://www.health24.com/Parenting/Child/Body/Vaccines-against-viral-diseases-20120721