Wonderful World of Rodents

Another cute Mouse pic

2008-05-09T20:02:00.001-07:00

This is one pretty mouse

Cute Mouse picture.

2008-05-09T19:58:00.000-07:00

To bad this photo has the watermark Logo on it. If i had some extra mad-money I'd buy some this pic and a few others. At least i can download it. Cut mouse huh?

Actually.. now that I've uploaded it, this pic doesn't have a logo on it. Cool.

For the kids.

2008-05-07T20:03:00.001-07:00

If any of you have kids this is for you (and them). I just thought this was kinda cute. MAybe you can print it out for your kids.

Baby Degu's!!

2008-05-07T19:53:00.001-07:00

I have never seen baby Degu's before so seeing this pic was a nice treat for me.

They sure are cute little things.

Thanks Nim for giving me this pic!

Family of Hedgies.

2008-05-06T20:34:00.001-07:00

Aren't they precious.

I'm gonna hide in this show

2008-05-06T18:23:00.000-07:00

Hedgies are so cute

Awwww

2008-05-06T18:21:00.000-07:00

Now that is a precious site~!

Northern Luzon Cloud Rats

2008-05-05T18:01:00.000-07:00

Just beautiful!

Pogonomys mollipilosus

2008-05-05T17:12:00.000-07:00

This little darling is called 'Pogonomys Mollipilosus'

Lets have a drink!

2008-05-05T17:03:00.000-07:00

I just thought this was a cute pic of hammies.

Tapir has a Capybara pillow.

2008-05-05T13:31:00.000-07:00

Look at the Tapir using the Capybara as a pillow. To cute. I adore Capybara's (world largest rodent/rat)

Beautiful Albino Squirrel

2008-04-30T15:22:00.000-07:00

This would be a dream come true for me to have an Albino Squirrel as a pet. I mean, I'd love to have a squirrel as a pet. I'm always watching out for orphaned baby squirrels around my house. But, to have an Albino... that would just be amazing!

Lazy Squirrel.

2008-04-26T16:59:00.001-07:00

He looks very comfy.

Cute pic of Mole Rat

2008-04-25T18:38:00.001-07:00

Fluffy Hamster

2008-04-24T13:49:00.000-07:00

Oh this picture is just to cute. He/She is posing, that's what makes it even more cute, like the hammie is saying "Yes, i knows i am adorables, so i will let yous take my picture"

Hangin on by a tail

2008-04-23T11:32:00.001-07:00

It's amazing what rodents can do with their tails

Mouse on Cat

2008-04-22T17:03:00.000-07:00

I don't think that cat is very happy. The mouse probably isn't but it makes for a cute pic.

Naked Mole ras are so precious.

2008-04-22T15:18:00.000-07:00

Aren't they the most adorable little critters. How can anyone thing they are ugly. Yes, they are unusual... but not *ugly*

Sorry for the 'Fotosearch' Logo. I got this pic from one of those 'Royalty Free' photo stock sites.

Some more various rodent photo's

2008-04-21T10:04:00.002-07:00

I got these all from the same website, so I'd like to give them credit: http://animalphotos.info/a/topics/animals/mammals/rodents/page/8/

2008-04-21T10:04:00.001-07:00

Various Rodent Pictures.

2008-04-19T13:56:00.000-07:00

Someone asked me "Where do you find ALL these pictures of rodents" Well... I said "Unfortunately i can't reveal my many sources for that would take away the uniqueness of 'Wonderful World of Rodents". He he he. But, looking for all these photo's (for all of my 3 animal blogs) could easily be an 8 hour job but, it's a labor of love job that's for sure. I enjoy every moment of it and i hope that the pay off is that you all enjoy 'Wonderful World of Rodents' and my other blogs. -Rebecca

Do me a favor... let me know which of these photo's you like the best. I'd really appreciate it :)

Smart Mouse

2008-04-19T13:30:00.000-07:00

To cute. I had a Mouse once that looked just like this cutie.

'Friendly' The Chipmunk- Pics removed

2008-04-19T12:10:00.000-07:00

Update:

'Friendly' the chipmunk photo's have been removed sadly because i received an e mail from the guy who took the photo's that he wants them down. While he was nice about it i think it is kinda sad. If i were him I'd want the wonderful story to reach more people and with my blog it would have. I just think it's rather lame for him to want them removed.

I have tons of professionaly style photos of my rats that i took and i let people use them all the time. The Friendly the chipmunk story is so wonderful you just think that the owner of the pictures and the owner of the story would want more people to see it and for more people to enjoy it.

While i respect his choise i think it's kinda sad that he asked me to take the down but he is entitled to do this. Poor Friendly, now all the people who view my blog won't be able to enjoy the story. I will not put the link up to the story.

-Rebecca

Guinea Pig Town

2008-04-19T10:52:00.000-07:00

This is the Guinea Pig enclosure at the Edmonton Valley Zoo.

I wish there was more info with the photo but there wasn't. I'd like to know if these were rescues or just an exhibit at the zoo. Anyone know?

I GOTS A SNACKS

2008-04-18T13:06:00.000-07:00

To cute! He sure looks happy doesn't he?

Found an interesting 'Small Animal' Website

2008-04-18T10:30:00.001-07:00

I just came across this Small Animal website and thought I'd share:

http://animal-world.com/encyclo/critters/critters.htm

No Cheese- I'm A Mouse

2008-04-18T10:03:00.000-07:00

Article:

Mice, it seems, get cheesed off with cheese and would much prefer chocolate.

According to scientists, mice don't like cheese after all and would rather have food with high sugar content.

Mice prefer high sugar food

The subject has been exercising researchers from Manchester Metropolitan University and the Stilton Cheese Makers Association.

As part of a wider study into animals and food, they found that a mouse's diet is primarily made up of grains and fruit.

It found that they would reject something as strong in smell and rich in taste as cheese.

Dr David Holmes, an animal behaviourist from the university, said: "Clearly the supposition of mice liking cheese is a popular premise.

"Mice have evolved almost entirely without cheese or anything resembling it.

"Mice respond to the smell, texture and taste of food and cheese is something that would not be available to them in their natural environment and therefore not something that they would respond to."

Nigel White of the Stilton Cheese Makers Association said: "Blue Stilton cheese has a very distinctive aroma and has a huge fan base across the world but mice are clearly not among that."

Or even cheddar, it seems.

ROTFL

2008-04-18T08:54:00.000-07:00

"I gots me peanutz butters"

Gorgeous!

2008-04-18T08:33:00.000-07:00

A beautiful Squirrel

2008-04-18T08:27:00.000-07:00

Thought this was a nice photo of a Squirrel

Various Rodent Art

2008-04-16T19:30:00.001-07:00

Here is some Rodent Art i can across tonight.

If you'd like to purchase any of these, they are all available at Art.com. Type in 'rodents'

This is quite pretty

2008-04-16T14:08:00.001-07:00

Some pretty art.

There's a Rodent World?

2008-04-16T13:57:00.001-07:00

http://www.flickr.com/photos/joyfuljoy/102026516/

WOW, I'd love to visit here.

The only info with the photo says "The entrance to Rodent World at the Zoobic Park of Subic Bay Freeport Zone" I have no idea what that means however.

Anyone know where this is? Or has anyone visited here? Anywhere i can get more info on it?

Ps... sometimes i am unable to download a photo from Flickr, does anyone know how i can accomplish this? I think someone once told me how to but i can't remember now. Any help would be appreciated.

BIG ONE!

2008-04-16T13:50:00.000-07:00

OMG lol. I'm not sure what type of rodent this is, there was no info with the photo. Anyone know? It's on the tip of my tongue! Great photo!

Hamartini

2008-04-15T18:57:00.000-07:00

I know this is totally photoshoped but it's kinda cute... in an unusual way.

Some beautiful Capybara's.

2008-04-14T18:28:00.001-07:00

These are one of my absolute favorite rats/rodents. And Capybara's are the worlds largest rat! Here are some great pics. Also I've included a link for even more pics!

To view more pics, go here:

http://commons.wikimedia.org/wiki/Category:Hydrochaeridae

My new Zazzle store.

2008-04-09T15:58:00.000-07:00

A store for the rat lover. All items made from my own rat photography and graphics designed by myself.

Http://www.zazzle.com/rsungodess

Also check out my cafepress store for older stuff
Http://www.cafepress.com/therodentstore.

Rebecca

We've seen this before..

2008-04-06T15:09:00.001-07:00

But maybe someone hasn't so i thought I'd put it on my blogs. It's just sooooooo cute

Cute rodent art.

2008-04-06T14:40:00.000-07:00

This painting has a little bit of all rodents in it. To cute!

Jerboa Video.

2008-04-03T14:00:00.000-07:00

I love the ears on these guys!

Mice prevail!

2008-04-03T13:57:00.001-07:00

Normally i wouldn't show or watch a video like this, i don't like watching any animal kill another animal even if it's a scorpian, for scorpians are one of the universes precious creatures as well. But, the mice prevail and i thought this was amazing. Whats the most amazing is how the venom doesn't affect the mice, they must have evolved to have a tolerance to the venom, pretty amazing and in the end they get their handsome richies.

Mice vs Scorpion

Rodents 'are smart enough'

2008-03-27T12:14:00.000-07:00

Interesting Read

Rodents 'are smart enough'
26/03/2008 14:22 - (SA)

(From News24.com)

-Thanks Dru for finding this article.

Tokyo - Rodents can be trained to use tools and understand their functions, a Japanese study said on Wednesday, challenging a view that only primates and some birds are smart enough.

Six adult "degus" rodents, a kind of small rat, were trained at a laboratory at the Japanese government-funded RIKEN research institute and all of them were able to use a tiny T-shaped rake to retrieve food, it said.

In the final stage of the 60-day experiment, they were pulling the tool towards themselves to hold onto it and then moving it to obtain food, the study showed.

"A conventional view holds that the use of tools is a high-level ability, but animals in the class of rodents can do it if they are trained accordingly," said Kazuo Okanoya, who heads the study team, told AFP.

The findings suggested that a wide range of animals could use tools, although it may be doubtful for fish, he said.

It is the first study in the world to demonstrate that rodents can be trained to manipulate tools in a systematic way and understand their functions, according to the team.

The study, published on the online edition of the US science journal PLos ONE on Wednesday with motion pictures, showed that trained rodents picked at random all understood the tool.

The study said that "socio-ecological" factors may be the most important, rather than innate physical characteristics, in whether animals can use tools.

In one test they were given two tools - a familiar functional rake and a non-functional tool that lacked a blade or had a raised blade. They chose the functional one without hesitation in most cases.

They chose the correct tool without being tricked by its colour or size, the study said.

As it is easier to study rodents than macaque monkeys - the conventional laboratory animal for such research - the team hopes to conduct more research into what is happening in the brain at a molecular level when animals use tools.

The degus, whose scientific name is Octodon degus, is originally from Chile.

Eastern Chipmunk

2008-03-25T18:46:00.004-07:00

Some great pictures of the Eastern Chipmunk

2008-03-25T18:46:00.003-07:00

2008-03-25T18:46:00.001-07:00

2008-03-25T18:45:00.005-07:00

2008-03-25T18:45:00.003-07:00

2008-03-25T18:45:00.001-07:00

Precious face

2008-03-24T13:05:00.000-07:00

This little Hammie has the cutest expression on it's face. Like it's saying "You have a food maybe?" or "Are you still loving me?"

On Top of The World.

2008-03-24T12:26:00.000-07:00

Jane Goodall holds a Giant Pouch Rat

2008-03-23T14:32:00.000-07:00

Jane Goodall with African Giant Pouch Rat...

This picture comes from an article and slide show at AnimalPlanet.com about the African Giant Pouch Rats that are helping clean out bombs and landmines.

Here is the link to the article and slide show:

http://animal.discovery.com/fansites/janegoodall/animalstalk/
photogallery/photogallery_09.html

Indiant Giant Squirrel.

2008-03-23T11:35:00.000-07:00

What a beautiful Squirrel. I've never even heard of an Indian Giant Squirrel, i just love the tri-coloring on this Squirrel.

Also the photographer who took this photo does wonderful photography. I did a spotlight of his/her work on 'Wonderful World of Animals' so if you'd like to see this photographers other work go to WWA- Http://wonderfulworldofanimals.blogspot.com

Cute Guinea Pig pic

2008-03-22T18:04:00.000-07:00

This was just to cute to pass up

Cute Degu Page

2008-03-22T14:07:00.000-07:00

Degu's are adorable and hear they make pretty good pets. Someone on one of the rat groups i belong to had a pet Degu but i can't remember who.. but, they said that their Degu made a great pet.

I found this cute Degu page and thought I'd pass it on: http://cutest.rodent.ever.com/?skip_login=1&sess_id=b378104293a464a9b73c41a58822f191

Handful of Rodents.

2008-03-21T19:13:00.000-07:00

I thought this was a great photo. There was no information with the photo so i don't know what species they are, maybe some sort of Chipmunk. The title of the photo is "Handful of Rodents" And it's by- Della Stock and it was on Deviantart.com

New Feature- what am i doing.

2008-03-21T14:46:00.000-07:00

I added a silly little widget to 3 of my blogs. It's Basically it just tells you what i am doing right now. You can see it lower down the the page- Scroll down and look to the right. When i want you to know what i am doing I'll updated it. LoL, it's kinda silly but fun.

Cute Blog.

2008-03-21T14:43:00.000-07:00

If you like to look at other blogs that are animal or rodent related like myself, here is a cute litle blog. It has other animals on it but it also has Rodents. I thought I'd share it with you.

http://weelittlebeasties.blogspot.com/

Species of the day- Pika

2008-03-21T12:29:00.000-07:00

Update: The Pika is our species of the day. I was doing Species of the day over at wonderful world of rats but i thought rodent species of the day would be better of here, so you will find that feature on WWRodents now.
Here is some info on the Pika: The name pika (archaically spelled pica) is used for any member of the Ochotonidae, a family within the order of lagomorphs, which also includes the Leporidae (rabbits and hares). One genus, Ochotona, is recognised within the family, and it includes 30 species. Pikas are also called rock rabbits or coneys. It is also known as the "whistling hare" due to its high-pitched alarm call when diving into its burrow. The pika may look like a hamster, but is actually a cousin of the rabbit. The name "pika" appears to be derived from the Tungus "piika", or perhaps from the Russian "pikat", to squeak. In the United States the pronunciation of the name is usually altered from /pika/ to /'paɪ·ka/, probably due to the spelling^{[citation needed]}. Habitat

Pikas are native to cold climates, mostly in Asia, North America and parts of eastern Europe. Most species live on rocky mountain sides, where there are numerous crevices to shelter in, although some also construct crude burrows. A few burrowing species are instead native to open steppe land. In the mountains of Eurasia, pikas often share their burrows with snowfinches, which build their nests there^[3].

In a January 2006 article in the Journal of Biogeography, archeologist Donald Grayson warned that human activity and global climate change appeared to be pushing the American pika population to ever-higher elevations and thus possibly toward extinction. Grayson studied pika habitation over the past 40,000 years in the region between the Sierra Nevada (U.S.) and Rocky Mountains. An earlier Journal of Mammalogy article reached a similar conclusion.

Characteristics

Pikas are small hamster-like animals, with short limbs, rounded ears, and short tails. They are about 18-20 cm in body length, with a tail less than 2 cm long, and weigh between 75 and 290 grams, depending on species. Like rabbits, after eating they initially produce soft green feces, which they eat again to extract further nutrition, before producing the final, solid, fecal pellets.

These animals are herbivores, and feed on a wide variety of plant matter. Because of their native habitat, they primarily eat grasses, sedges, shrub twigs, moss, and lichen.

Rock-dwelling pikas have small litters of less than five young, while the burrowing species tend to give birth to more young, and to breed more frequently, possibly due to a greater availability of resources in their native habitats. The young are born after a gestation period of between 25 and 30 days^[3].

Activity

Pikas are diurnal or crepuscular, with higher altitude species generally being more active during the daytime. They show their peak activity before the winter season. Pikas do not hibernate, so they rely on collected hay for warm bedding and food. Pikas gather fresh grasses and lay them in stacks to dry. Once the grasses dry out, the pikas take this hay back to the burrows for storage. It is not uncommon for pikas to steal hay from others; the resulting disputes are usually exploited by neighboring predators like ferrets and large birds.

Eurasian pikas commonly live in family groups and share duties of gathering food and keeping watch. At least some species are territorial. North American pikas (O. princeps and O. collaris) are asocial, leading solitary lives outside the breeding season.

Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Lagomorpha
Family:	Ochotonidae Thomas, 1897
Genus:	Ochotona Link, 1795

On a personal note.. Pika's are one of my favorite rodents. They are just too cute for words!

Oh my, What big ears you have

2008-03-20T21:12:00.000-07:00

Adorable photo of a Jerboa.

Adorable Dormouse.

2008-03-20T20:55:00.000-07:00

I got these adroable pictures of a Dormouse on Cute Overload (CuteOverload.com).

There was some info about this Dormouse with the pictures. It said;

'The UK Daily Mail' is reporting "That this anerable dormouse had to fatten up before going into hibernation mode [zzzzzzz] So rescue workers worked feverishly to stuff him full of delectabuhl ivy pollen and blackberries".

And "For some reason he also lives in a coconut apartment. "Dozey" is now sleeping peacefully and will wake up refreshed in April. I bet he'll have the tiniest of beards then."

I don't know to much about the Dormouse so i dug up some info from Wikipedia:

Dormice are rodents of the family Gliridae. (This family is also variously called Myoxidae or Muscardinidae by different taxonomists). Dormice are mostly found in Europe, although some live in Africa and Asia. They are particularly known for their long periods of hibernation.

Dormice are small for rodents, with a body length of between 6 and 19 centimetres (2.5 - 7.5 inches), and weighing between 15 and 200 grams. They are generally mouse-like in appearance, but with furred, rather than scaly, tails. They are largely but not exclusively arboreal animals, and are agile and well adapted to climbing. Most species are nocturnal. Dormice have an excellent sense of hearing, and signal each other with a range of different vocalisations^[1].

Dormice are omnivorous, typically feeding on fruits, berries, flowers, nuts and insects. Dormice are unique among rodents in that they lack a cecum, a part of the gut used in other species to ferment vegetable matter. Their dental formula squirrels, although they often lack premolars: is similar to that of

Dormice breed once or twice a year, producing litters with an average of four young after a gestation period of 21-32 days. They can live for as long as five years. The young are born hairless, and helpless, and their eyes do not open until about eighteen days after birth. They typically become sexually mature after the end of their first hibernation. Dormice live in small family groups, with home ranges that vary widely between species, and depending on the availability of food^[1].

One of the most notable characteristics of those dormice that live in temperate hibernation. Dormice can hibernate six months out of the year, or even longer if the weather remains sufficiently cool, sometimes waking for brief periods to eat food they had previously stored nearby. During the summer, they accumulate fat in their bodies, to nourish them through the hibernation period^[1]. zones is

It is from this trait that they got their name, which comes from Anglo-Normandormeus, which means "sleepy (one)"; the word was later altered by folk etymology to resemble the word "mouse". The sleepy behaviour of the Dormouse character in Lewis Carroll's Alice's Adventures in Wonderland also attests to this trait.

Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Rodentia
Suborder:	Sciuromorpha
Family:	Gliridae

Beautiful Guinea Pig Pictures.

2008-03-20T18:51:00.000-07:00

I found these on Flickr and i just had to share..
I'm thinking these were taken in the spirit of Easter.

Rodent Photo's

2008-03-20T15:54:00.000-07:00

One of the features I'll have here at WWR are daily pictures of rodents but not just pictures... GREAT PICTURES. Just like i do on my other blogs. I plan to someday have biggest collection of wonderful rodent pictures than anywhere else on the net.

Above are some lovely photo's of various rodents.

If you're wondering what kind of rodents they are; from top to bottom: Capybara (Worlds largest rodent), Mouse, Porcupine, Guinea Pig, Gerbil, Chipmunk and another Capybara at the bottom. I love the top photo, it looks like a momma Capybara kissing it's baby ... Awwwww!

Hope you enjoyed these. Check back often for I'll probably post photo's a few times a day.

Naked Mole Rat

2008-03-20T15:36:00.001-07:00

This is a great picture of a Naked Mole rat.

Here is a little info about the Naked Mole Rat:

There are approximately 30 different kinds of mole rats. The best known is probably the naked mole rat, whose hairless, tubular, wrinkled body makes it appear a bit like a tiny walrus—or perhaps a bratwurst with teeth. Naked mole rats are rodents, but they live in communities like those of many insects. Several dozen rats live together in colonies led by one dominant rat—the queen. As in some insect species, the queen is the only naked mole rat female to breed and bear young. Worker animals dig the burrows that the whole clan inhabits, using their prominent teeth and snouts. They also gather the roots and bulbs for the colony to eat. Other rats tend to the queen. Most other types of mole rats live on their own or in small families. Blind mole rats do have tiny eyes, but they are located beneath their skin and fur. These animals rely on sensitive hairs to feel their way through their underground burrows. Though mole rats spend most of their time excavating and foraging in their burrows, they occasionally emerge to search for seeds or other plants. Mole rats have a wide geographical distribution and can live below sea level or high on mountainside plains. Because of their burrowing lifestyle, they do prefer areas with sandy or loamy soil. Many mole rat species are found in sub-Saharan Africa. Blind mole rats are found primarily in southeastern Europe, the Middle East, and Mediterranean North Africa.

Type: Mammal

Diet: Herbivore

Size: Head and body, 3 to 13 in (8 to 33 cm); Tail, up to 3 in (8 cm)

Weight: 1 oz to 3.3 lbs (28 g to 1.5 kg)

Size relative to a tea cup:

Introduction to Rodentia.

2008-03-20T11:53:00.000-07:00

Good article explaining Rodentia..

Introduction to the Rodentia

The single largest group of mammals is the Rodentia. Most non-flying mammals are rodents: there are about 1,500 living rodent species (out of about 4,000 living mammals overall). Most people are familiar with mice, rats, hamsters, and guinea pigs, which are commonly kept as pets. The Rodentia also includes beavers, muskrats, porcupines, woodchucks, chipmunks, squirrels, prairie dogs, marmots, chinchillas, voles, lemmings, and many others. (Incidentally, the Rodentia does not include rabbits; rabbits differ from rodents in having an extra pair of incisors and in other skeletal features. Rabbits, hares, and a few other species make up the Lagomorpha. Shrews, moles and hedgehogs are also not rodents; they are classified in the Insectivora.)

Rodents are found native on all continents except Antarctica. One particular family of rodents, the Muridae, contains over 1100 species: over a quarter of all mammal species are rats, mice, voles, muskrats, lemmings, hamsters, gerbils, and other members of the Muridae. However, rodents show perhaps their greatest diversity of form in South America, which was an isolated continent for much of the Cenozoic. A few of these distinctive South American rodents include mountain viscachas, rabbit-like forms that inhabit dry mountainous regions; Patagonian cavies, very rabbit-like, fast-running forms with elongated ears and short tails; the coypu or nutria, a large marsh-dwelling rodent that has been introduced into North America and is hunted for its fur; and various burrowing forms such as pacas and tuco-tucos. Other South American rodents include guinea pigs, chinchillas, and New World porcupines (one species of which has dispersed into North America). The capybara (shown

at left), yet another South American species, is the largest living rodent. About the size of a pig, and reaching a maximum weight of 50 kg (110 pounds), the capybara is truly a rodent of unusual size. Capybaras live along rivers in the llanos (plains) of South America, and are often hunted or even ranched for their meat.

Despite their great species diversity, all rodents share common features. Rodents have a single pair of incisors in each jaw, and the incisors grow continually throughout life. The incisors have thick enamel layers on the front but not on the back; this causes them to retain their chisel shape as they are worn down. Behind the incisors is a large gap in the tooth rows, or diastema; there are no canines, and typically only a few molars at the rear of the jaws. Rodents gnaw with their incisors by pushing the lower jaw forward, and chew with the molars by pulling the lower jaw backwards. In conjunction with these chewing patterns, rodents have large and complex jaw musculature, with modifications to the skull and jaws to accommodate it. Like some other mammal taxa, but unlike rabbits and other lagomorphs, male rodents have a baculum (penis bone). Most rodents are herbivorous, but some are omnivorous, and others prey on insects. Rodents show a wide range of lifestyles, ranging from burrowing forms such as gophers and mole rats to tree-dwelling squirrels and

gliding "flying" squirrels, from aquatic capybaras and muskrats to desert specialists such as kangaroo rats and jerboas, and from solitary organisms such as porcupines to highly social organisms living in extensive colonies, such as prairie dogs (left) and naked mole rats.

Rodents cost billions of dollars in lost crops each year, and some are carriers of human diseases such as bubonic plague, typhus, and Hanta fever. However, various rodent species are economically important as sources of food or fur in many parts of the world, and others are used extensively in biomedical research.

Many early mammal taxa were superficially rodent-like, such as the extinct multituberculates. However, true rodents first appear in the fossil record towards the end of the Paleocene epoch. Their ancestry is probably to be found among a group of small fossil mammals known as anagalids, which may also have given rise to the Lagomorpha. The living rodent with the most archaic characters, most like the common ancestor of the Rodentia, is the sewellel or mountain beaver (which is not a true beaver at all) of the northwestern United States. During the Oligocene, the South American rodents began their great evolutionary radiation. By the Miocene, very modern-looking squirrels had evolved, as had the murids. Murids began their spectacular radiation in the Pliocene.

Noteworthy Pleistocene rodents include the extinct giant beaver, Castoroides, which was about the size of a bear. More prosaic rodent fossils from this time period, notably the teeth of voles and mice, have become important in reconstructing global climate patterns as well as in fine-scale studies of evolution.

Great Pic

2008-03-20T11:44:00.000-07:00

This is an awesome pic. Not sure what type of Rodent it is, probably some form of Hamster, there was no info with the picture.

Mouse Intelligence Measured

2008-03-20T10:57:00.000-07:00

Mouse intelligence measured

Rodent 'g' might reveal genes for intellect.

HELEN PEARSON

Some mice are cleverer than others, say US neuroscientists. Their rodent equivalent of an IQ test might fuel the controversial pursuit for genes linked to human intelligence.

Scientists have long used a factor called general intelligence or 'g' to rate people's brainpower. The measure spans verbal, logical and mathematical tasks - so a person with a big 'g' tends to score highly in all intelligence quotient (IQ) tests, and do well in school and work.

Mice have a version of 'g', according to a team led by Louis Matzel of Rutgers University in Piscataway, New Jersey1. Animals that come top in one learning test often score better on others, they found: a maze champion might be a sniffing sensation too. "Once in a while you come across one that's absolutely stunning," says Matzel.

This might sound obvious - but because the tests are so laborious, few people have examined whether there are general differences between individual animals. Many studies average and compare the scores of groups of mice using one or two learning tasks.

Matzel's results imply that some mice have a general learning ability rather than, say, just being good at navigating or discriminating. This factor seems to underpin around 40% of the difference in task performance between individual mice, Matzel's team found.

Human 'g' also accounts for about 40% of variation in intelligence tests. "It's a terrifically important paper," says Robert Plomin, who studies intelligence at King's College, London. "It's by far the most stringent test of the hypothesis that you can find 'g' in mice."

Sceptics point out that Matzel's general learning factor may actually be a measure of a mouse's curiosity, motivation or athletic ability. "You might be testing what it's easy to test," warns psychologist Howard Gardner of Harvard University in Cambridge, Massachusetts.

G for genes

If the idea holds up, the mouse version of 'g' could help researchers to hunt for genes that underlie mouse learning power and, perhaps, human intelligence. Many studies have shown that 'g' is partly inherited, but it is difficult to track down relevant genes in people.

Matzel is already comparing the brain genes that are active in mice with high and low 'g' values. These might help re-wire nerve cells or boost signal firing.

Many experts are wary of this line of research, however. It raises the prospect that people might be labelled as clever or stupid on the basis of their genetic code, or that parents could screen embryos for intelligence genes.

Geneticists counter that such studies might instead reveal ways in which we can boost intelligence using, for example, nutrition or education. "They are difficult issues - but they're not as worrisome as we think," Plomin says.

Others argue that 'g' is a poor measure of human intelligence anyway. IQ tests, they say, are too crude to pick up individual talents. Gardner, for example, proposes that there are several distinct types of intelligence, such as logical, musical and interpersonal.

References
Matzel, L. M. et al. Individual differences in the expression of a 'general' learning ability in mice. Journal of Neuroscience, 23, 6423 - 6433, (2003). |Article|

Welcome to Wonderful World of Rodents

2008-03-20T10:53:00.000-07:00

This is the new sister blog to 'Wonderful world of Animals' and Wonderful World of Rats." Wonderful world of Rodents is just like my other two animal related blogs but it focuses on the vast world of Rodents. While Rats are my main passion in life i love all rodents.

As i was searching for things on the net for WWR and WWA i kept coming across great Rodent stuff and i didn't want to bombard my animal or rat blog with rodent information and articles, pictures etc so i thought I'd make a blog that focused on rodents.

Welcome to WWRodents, please enjoy and check back often.

-Rebecca
Creator of Wonderful World of Animals, Wonderful World of Rats, Nubby's Wonderful World.