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Author: mstack229 One star, 50 posts Add to my Favorite Fools Ignore this person (you won't see their posts anymore) Number: of 24987  
Subject: Self-Made Cells Date: 1/30/2001 12:26 AM
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Self-Made Cells Show Life Could Come From Space
Updated: Mon, Jan 29 05:13 PM EST

By Maggie Fox, Health and Science Correspondent
WASHINGTON (Reuters) - Tiny little bubbles that can build themselves in the freezing vacuum of space suggest that life, or the seeds of life, could have originated out in the cosmos, scientists said on Monday.
In an experiment that duplicated the harsh conditions of space -- cold temperatures, no air, plenty of radiation -- they managed to get artificial cell membranes to form.

The membranes, which resemble soap bubbles, could act as primitive cell walls, David Deamer, a biologist who specializes in membranes at the University of California Santa Cruz, said in a telephone interview.

"This wall is semi-permeable. All membranes are semi-permeable, so that things like water and oxygen get in and out very easily," said Deamer, who worked on the study. "That is what life requires -- it needs to have an inside that is not totally shut off from the outside."

Writing in Tuesday's issue of the Proceedings of the National Academy of Sciences, the researchers said organic compounds from interstellar space might have kick-started life on Earth.

Deamer said the compounds have been found on dust from meteorites carried to Earth, and years ago these compounds were found to "self-assemble" into soapy, water-repelling bubbles.

When the U.S. space agency NASA started its astrobiology program -- a search for life in space -- researchers teamed up to see what it would take to make a cell in space.

"Scientists believe the molecules needed to make a cell's membrane, and thus for the origin of life, are all over space," Louis Allamandola of NASA's Ames Research Center in California, who led the study, said in a statement. "This discovery implies that life could be everywhere in the universe."

SIMPLE, COMMON COMPOUNDS The researchers used simple, common compounds, which self-assembled into something that looked very much like a vesicle or cell membrane.

"This process happens all the time in the dense molecular clouds of space," Allamandola said.

Such compounds could easily have been brought to Earth by a meteorite or asteroid. "The delivery of these compounds could well have been critical to the origin of life on Earth," Allamandola said.

"Maybe these molecules were just the raw lumber lying around that allowed origin-of-life chemicals to move in and set up housekeeping or construct their own houses," added Jason Dworkin, a post-graduate researcher at NASA who did much of the work on the study.

The next step is to see if these little bubbles can support cell-like activity inside and Deamer said they might.

"We are trying on purpose to put things like DNA and RNA inside the vesicles," he said.

DNA and RNA are the genetic basis of life, with DNA carrying the basic instructions for cellular activity and RNA carrying it out.

"In a sense we are trying to make, not an artificial form of life because we are nowhere near this, but a model of what would have led to early life," Deamer said.

"We have captured a gene on DNA in a little lipid (fatlike) vesicle. We also captured an enzyme that can use that gene to make RNA. That's all inside a little cellular vesicle."

They are feeding it with chemicals known to support cell activity and so far it is working, he said.


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Author: beckyz51 Big red star, 1000 posts Old School Fool Add to my Favorite Fools Ignore this person (you won't see their posts anymore) Number: 89 of 24987
Subject: Re: Self-Made Cells Date: 2/10/2001 12:25 PM
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mstack229,
Cool! But who's to say those bubbles didn't start out on earth and eventually blow back or whatever?
I guess, as a Christian, I see things differently. But I love to hear about these kinds of things. I can't imagine being able to actually SEE a DNA. Hope those scientists know how lucky they are.
Becky

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Author: nf Big red star, 1000 posts Old School Fool Add to my Favorite Fools Ignore this person (you won't see their posts anymore) Number: 104 of 24987
Subject: Re: Self-Made Cells Date: 2/13/2001 12:49 AM
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Becky,

In the bible,I am brutally paraphrasing here."surely
the rocks will cry out" Or "the land will not give forth"
I belive everything is alive in one way or another.And
don't see the point in where the bubbles came from.I want to know how for instance a complex life form "evolved" when only the finished product can survive and reproduce.And why you can breed for hundreds of years (hogs for instance,I was a hog farmer) and get
almost anything you want with time but it is still a hog!,,,Lucy?give me a break.

And did anyone check and see if black moths existed
before they started burning coal?Or don't they want to?
2nd time I asked this one,no reply.

As for the big bang,GOD SPOKE!! BANG!! IT HAPPENED :).

Chris

PS yes I am still revuing past posts.I am glad so much
brain power is here.


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Author: dcarper Big gold star, 5000 posts Add to my Favorite Fools Ignore this person (you won't see their posts anymore) Number: 105 of 24987
Subject: Re: Self-Made Cells Date: 2/13/2001 10:19 AM
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And why you can breed for hundreds of years (hogs for instance,I was a hog
farmer) and get
almost anything you want with time but it is still a hog!


Chris, keep in mind that hundreds of years is a very short time when speaking about change. It is sorta like discovering compound interest (this is an investing site, after all), and investing money. Then taking it out 1 second later, and saying "this compounding thing is bogus, my money didn't change much."

David

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Author: nf Big red star, 1000 posts Old School Fool Add to my Favorite Fools Ignore this person (you won't see their posts anymore) Number: 106 of 24987
Subject: Re: Self-Made Cells Date: 2/13/2001 10:35 PM
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And why you can breed for hundreds of years (hogs for instance,I was a hog
farmer) and get
almost anything you want with time but it is still a hog!

Chris, keep in mind that hundreds of years is a very short time when speaking about change. It is
sorta like discovering compound interest (this is an investing site, after all), and investing money.
Then taking it out 1 second later, and saying "this compounding thing is bogus, my money didn't
change much."

David
=====

David,

I will expand.In say 4,000 years (written time)hogs (not just hogs)
have been breed on purpose for change.You can change your herds makeup dramatically in one generation by changing your boars.You can go from medium size well
rounded to longer (like a hotdog) leaner (less fat)more muscled
offspring.In one generation with the same sows!I said
200 years because hogs 200 years ago were bred to produce fat.They looked like barrels back then all of
them.Hmm pork barrel spending?Now they are the other white meat.(very little fat)Pork does not marble its fat as does beef....Marbling is haveing little bits of
fat spred thru the meat.That is why pork is dry,dry,dry.Hogs have always had lean meat. They carry
fat in layers around the muscles but mostly on the back
neck and belly.The new white meat is advertiseing "balony"....At 2.3 litters per year and 14 pigs per litter (my average) 4,000 years gives a lot of interist
(yes this is an investing site) 32.2 pigs per sow per
year x all sows involved x 4,000.And it is a hog!Not a
bird!

The evolution croud started with thousands of years,
then millions then billions,dare I say trillions?
Every time they have a problem they just add a huge amount of time and say,it could happen.I wish my moneys
interist was compounding on such a scale :).

Chris













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Author: dcarper Big gold star, 5000 posts Add to my Favorite Fools Ignore this person (you won't see their posts anymore) Number: 107 of 24987
Subject: Re: Self-Made Cells Date: 2/14/2001 12:23 PM
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Chris,

(most of previous post snipped)

..At 2.3 litters per year and 14 pigs per litter (my average) 4,000
years gives a lot of interist


Actually, the critical number is the amount of time between generations. I'm not a pig farmer, so I don't know how long it takes, but I would guess that it is at least a year, and probably closer to two, between generations. In other words, from the day a pig is born, you can expect 1-2 years before it bears offspring. (like I say, I don't know, my numbers could be way off, but I doubt that I am way high).

As to it still being a hog, you are most likely correct. Of course, since there are no 4000 year old hogs around to compare them to, we don't know for sure that they could still mate and produce fertile offspring. More importantly, at some point in the past, all pigs were wild. Some wild pigs were domesticated. So the question might be, can today's domesticated pigs breed with the wild pigs that descended from the ones that escaped being captured when domestication was beginning. (I don't know the answer to this BTW. I'm not sure is a farm pig can breed with a wild boar, or warthog, or javalina).

While it is true that for 4000 years, they are still hogs, the meaning of hog may have evolved also. Evolution can only be measured when a species branches, which can only occur with some form of isolation. Then the populations may or may not diverge. If, after being isolated, the two groups are recombined and allowed to interbreed, infertile offspring will indicate that they are no longer of the same species. Which one will you then say has changed? Of course, the correct answer is both.

David
(hope this makes sense. Sometimes I wonder about myself)

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Author: nf Big red star, 1000 posts Old School Fool Add to my Favorite Fools Ignore this person (you won't see their posts anymore) Number: 110 of 24987
Subject: Re: Self-Made Cells Date: 2/14/2001 8:55 PM
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Actually, the critical number is the amount of time between generations. I'm not a pig farmer, so I
don't know how long it takes, but I would guess that it is at least a year, and probably closer to
two,

Six months,no problem.

I'm not sure is a farm pig can breed with a wild
boar, or warthog, or javalina).

Wild boar (razorback) yes if you want to really mess
up your genetics.Warthog,maybe laying down (hogs stand)
simular heigth is important.And I have no idea what would happen.What is a javalina?

Very good post I think I'm starting to get it (evolution).

Chris

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Author: dcarper Big gold star, 5000 posts Add to my Favorite Fools Ignore this person (you won't see their posts anymore) Number: 114 of 24987
Subject: Re: Self-Made Cells Date: 2/15/2001 9:16 AM
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What is a
javalina?


I forget, you're from the north. A javalina is also called a collared peccary (sp?). It is a small(18-24") wild pig like animal of the desert. Common in Arizona, more so I think in Mexico. In all honesty, I'm not sure how closely related to pigs they are, but they sure look like pigs.

I was thinking more along these lines and wondering - do you know if wild boars are from a line that has always been wild, or if they are descended from domesticated hogs that escaped?

Six months, huh? I didn't really expect it to be that short. But hey, what's a factor of two between friends?

David

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Author: amynorcom Big red star, 1000 posts Add to my Favorite Fools Ignore this person (you won't see their posts anymore) Number: 115 of 24987
Subject: Re: Self-Made Cells Date: 2/15/2001 11:36 AM
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A javalina is also called a collared peccary (sp?). It is a small(18-24") wild pig like animal of the desert. Common in Arizona, more so I think in Mexico. In all honesty, I'm not sure how closely related to pigs they are, but they sure look like pigs.
I was thinking more along these lines and wondering - do you know if wild boars are from a line that has always been wild, or if they are descended from domesticated hogs that escaped?
-dcarper

Oh my gosh, you guys have to stop talking about fun stuff like this or I'll never get my calculus project done. : )

Peccaries are in the same sub-order as pigs (Suina), as are hippos, but are not in the same family (Suidae) (warthogs and babyrusa, for instance are in the pig family). Domestic pigs evolved from wild boars, not the other way around.

===

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla

Artiodactyls are even-toed hoofed mammals, and include Bovids (Wild Cattle), Camels, Deer, Pronghorns, Giraffes, Hippopotami, Peccaries, and Pigs.

The last three (bold) are families in the sub-order...

Suina

The first suids appeared in the Oliogocene; pigs evolved in the Old World and peccaries in North America. Evolution of the group involved increased size, lengthening of the skull, and development of large outwardly curving tusks. The peccaries emphasized development of more cursorial body conformation rather than size as in Old World pigs. Hippos, the remaining member of the Suina, arose from advanced anthracotheres relatively recently in the late Pliocene. Most pig-like artiodactyls are omnivores. The two notable exceptions are the babirussa which has developed some measure of pre-gastric fermentation and the hippopotami which assumed a much larger size with their adoption of a basically herbivorous diet. The Suina include three families; Suidae (true pigs), Tayassuidae and Hippopotamidae. Most members are found in the Old World.

Family: Suidae

Domestic pigs arose from selective breeding of Sus scrofa, the European wild boar, and Sus cristatus, a closely related species in Asia. Other wild Asian forms are the pygmy hog and the babirusa, an unusual form with advanced pregastric fermentation. Modern African suids include 3 species. The bushpig (Potamochoerus porcinus) is the most generalized species found throughout the equatorial forest and moister eastern and souther savannas. They require relatively dense vegetation and moist and hence soft soils. The giant forest hog (Hylochoerus meinertzhageni), the largest living suid, is distributed in dense equatorial and montane forests. The warthog (Phacochoerus aethiopicus) is more familiar because of its diurnal habits and preference for wooded and open savannas.
Breakdown of Suidae:
Babyrousinae
Babyrousa
Babyrousa babyrussa Babirusa
Phacochoerinae
Phacochoerus
Phacochoerus aethiopicus Desert warthog
Phacochoerus africanus Common warthog
Suinae
Hylochoerus
Hylochoerus meinertzhageni Giant forest hog
Potamochoerus
Potamochoerus larvatus Bush pig
Potamochoerus porcus Red river hog
Sus
Sus barbatus Bearded pig
Sus bucculentus Vietnam warty pig
Sus cebifrons Cebu bearded pig
Sus celebensis Celebes pig, Sulawesi warty pig
Sus philippensis Philippine warty pig
Sus salvanius Pygmy hog
Sus scrofa Eurasian wild boar
Sus verrucosus Javan warty pig


Family: Tayassuidae

The peccaries (Sowls 1984) are restricted to the New World. Until recently, it was believed that only two species remained, the collared peccary (Tayassu tajacu) and the white-lipped peccary (Tayassu albirostris). However, a new species (Catagonus wagneri) has been recently discovered in Paraguay.
Breakdown of Tayassuidae:
Catagonus
Catagonus wagneri Chacoan peccary
Pecari
Pecari tajacu Collared peccary, Javelina
Tayassu
Tayassu pecari White-lipped peccary


Family: Hippopotamidae

Hippopotami are now endemic to the Ethiopian region. The familiar Hippopotamus amphibius is widely distributed in lakes and rivers where it spends much of its daylight hours partially or completely submerged. Most feeding is done at night on coarse grasses which are often onsiderable distances from loafing pools. The less social dwarf hippo (Choeropsis) is found in forested areas of Western Africa.
Breakdown of Hippopotamidae:
Hexaprotodon
Hexaprotodon liberiensis Pygmy hippopotamus
Hippopotamus
Hippopotamus amphibius River hippopotamus


http://www.deer.rr.ualberta.ca/library/phylogeny/Phylogeny.html#RTFToC23

http://www.ultimateungulate.com/artiodactyla.html

===

Here is a page that has cool links (including pics) to any artiodactyl you could ever imagine in your wildest dreams. ; ) Just scroll down for the cute (and not-so-cute) piggies:

http://www.birminghamzoo.com/ao/eventoed.htm

I was totally deprived of the study of mammals in my college Zoology class, because we spent all our time breaking down the lower animals...

http://www.sidwell.edu/us/science/vlb/class/animalia/animal-tree.jpg

...so this is great fun for me!

Take care,
Amy


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Author: nf Big red star, 1000 posts Old School Fool Add to my Favorite Fools Ignore this person (you won't see their posts anymore) Number: 119 of 24987
Subject: Re: Self-Made Cells Date: 2/15/2001 11:31 PM
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I was thinking more along these lines and wondering - do you know if wild boars are from a line
that has always been wild, or if they are descended from domesticated hogs that escaped?
========
David,

Hogs are impossible to confine.They never stop destroying things. They are smart and curious also.
When you wake up and see a hog walk past the window munching some veggies,you are having a bad day.And it
just started.1 A hog is out and knows how to get out.
Also others may have observed the escape and "learned".
2 Other hogs may have unwittingly contributed to the
escape and figger it out on some future date.Escape(On a day
which you are off farm) And make a mass mess. 3 "The veggies" Your garden is destroyed.

A domestic hog can do just fine in the wild.

I know I am reinforcing your point.OK with me.

PS Cows (bovine?) are as dumb as a rock.(sorry rocks).

Chris

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Author: nf Big red star, 1000 posts Old School Fool Add to my Favorite Fools Ignore this person (you won't see their posts anymore) Number: 120 of 24987
Subject: Re: Self-Made Cells Date: 2/16/2001 12:30 AM
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Most pig-like
artiodactyls are omnivores.
======
I can attest to that! The darn things eat everything!
I saw one chewing on a rock,and happy.Rutting for worms or roots or whatever.They love grass,barn siding,car trim,tractor wiring,walking around in my neighbors fresh pored cement,etc.If you have any questions as to the nature of the beast ask me.One of
them was "a best frend" and I am including humans.

Chris

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Author: beckyz51 Big red star, 1000 posts Old School Fool Add to my Favorite Fools Ignore this person (you won't see their posts anymore) Number: 122 of 24987
Subject: Re: Self-Made Cells Date: 2/16/2001 8:52 AM
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Amy,
I'm going to admit I've totally forgotten all this 'family', sub-family stuff.
How do 'species'(all the Bible gives us) relate to all this. My contention is that there IS evolution within species, but no evolving into another species, by natural means any way. So, for instance, could the hippo, peccaries and pigs (if they could find a way!) reproduce?
And don't even get me going on pigs on the loose! My yard looked like a tiller went thru! My flowers! He was a lazy pig, never found my veggies. Ha! But I liked it anyway, gave the dumb thing bubble baths with the kids! It's just that no strings attached love like God has for us. He says, when the Israelites are worshipping rocks, etc. AGAIN, 'They are but dust.' And I can picture Him sighing and shaking His head. Becky


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Author: dcarper Big gold star, 5000 posts Add to my Favorite Fools Ignore this person (you won't see their posts anymore) Number: 123 of 24987
Subject: Re: Self-Made Cells Date: 2/16/2001 11:22 AM
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Peccaries are in the same sub-order as pigs (Suina), as are hippos,

Amy,
thank you for a very informative post. I've learned more about pigs in the last couple of days than I ever dreamed!

Now about hippos; I always thought they they were related to elephants. Was I mistaken? Or are elephants also related to pigs, maybe just a little farther up the tree?

Nice to have someone with a biology background here. Kazim and I were both physics majors, and I for one never took biology after high school.

David

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Author: amynorcom Big red star, 1000 posts Add to my Favorite Fools Ignore this person (you won't see their posts anymore) Number: 124 of 24987
Subject: Re: Self-Made Cells Date: 2/16/2001 3:45 PM
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Hey Becky,

I'm going to admit I've totally forgotten all this 'family', sub-family stuff.
How do 'species'(all the Bible gives us) relate to all this. My contention is that there IS evolution within species, but no evolving into another species, by natural means any way. So, for instance, could the hippo, peccaries and pigs (if they could find a way!) reproduce?


Ok, first things first; an example of the taxonomy of the Philippine warty pig :

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Sub-Order: Suina
Family: Suidae
Genus species: Sus philippensis
Common Name: Philippine warty pig

Philippensis is the species name in this example, but we use the genus and species names together to label living things. This is how all living things are classified.

The actual definition of a species is simply a group of organisms that can mate and produce fertile offspring.

Here's m-w.com:

===

Main Entry: 1spe·cies
Pronunciation: 'spE-(")shEz, -(")sEz
Function: noun
Inflected Form(s): plural species
Etymology: Middle English, from Latin, appearance, kind, species, from specere to look -- more at SPY
Date: 14th century

d (1) : a category of biological classification ranking immediately below the genus or subgenus, comprising related organisms or populations potentially capable of interbreeding, and being designated by a binomial that consists of the name of a genus followed by a Latin or latinized uncapitalized noun or adjective agreeing grammatically with the genus name (2) : an individual or kind belonging to a biological species

http://www.m-w.com/

===

So the answer to this one...

So, for instance, could the hippo, peccaries and pigs (if they could find a way!) reproduce?

...is no way, girlfriend. They'd never interbreed in the wild, and you have to stay within the same species to produce non-sterile offspring.

Kingdom
Phylum
Class
Order
Sub-Order <--- hippos, pigs, and peccaries share this
Family
Genus
Species<--- which is waaaay different from this.


My contention is that there IS evolution within species, but no evolving into another species, by natural means any way.

I don't think I understand what you mean in this sentence. Maybe you could elaborate on your definition of evolution/evolving.

Take care,
Amy

P.S. I'm jealous that all you guys got to have pet pigs. I've wanted a pig since age 6 when I read Charlotte's Web.




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Author: amynorcom Big red star, 1000 posts Add to my Favorite Fools Ignore this person (you won't see their posts anymore) Number: 125 of 24987
Subject: Re: Self-Made Cells Date: 2/16/2001 6:38 PM
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David,

Now about hippos; I always thought they they were related to elephants. Was I mistaken? Or are elephants also related to pigs, maybe just a little farther up the tree?

I've always thought that hippopotami, elephants, and rhinoceroses were closely related too, but they're not, anymore than they're all closely related to anteaters, giraffes, warthogs, gazelles, or manatees; all ungulates (hoofed mammals).

Hippos are like pigs, rhinos are like horses, and elephants are in their own order, which has only one family and two species (Indian elephants and African elephants). Well, actually, there's a cool thing that shows all the probiscids that have ever existed, and some of the extinct ones were in distinctly different families:

===

Order: PROBOSCIDEAE

The Tethytheria include the divergent proboscideans (elephants) and the Sirenia (sea cows). The earliest proboscidean arose in Palaeocene Africa and radiated into a multitude of some 300 species by the beginning of the Miocene. These species have been grouped into four super-families; the Deinotheridae, Gomphotheridae, Mastodontidae, and Elephantidae. [Visit David Atkin's site: http://gwis2.circ.gwu.edu/~atkins/newwebpages/Mammalia/proboscidea/elephants.html ]

Family:Deinotheridae (extinct)

Deinotherium appeared in the Eocene, an animal almost the size of modern elephants but with tusks curving downward from the lower jaw. They became extinct in Eurasia during the Pliocene but survived in Africa into the Pleistocene.

Family: Gomphotheridae (extinct)

The gomphotheres flourished from about 38 million years BP until the Holocene. Paeleomastodon, one of the earliest members, had short tusks on both upper and lower jaws and the trunk was poorly developed. Stegomastodon, a more recent gomphothere, had tusks of unusual length measuring almost three-quarters as long as its body

Mastodontidae (extinct)

Mastodonts first appeared in Eurasia during the lower Miocene and spread to Africa and North America and subsequently South America. They survived in the New World until about 6000 BP. Despite their numerical abundance as evidenced in the large numbers of fossil remains in North America, they did not appear to be widely hunted by early Man, although evidence points to greater use in South America. The mastodonts differed from the mammoths and modern elephants in the structure of their molars. Mastodonts had rounded cusps or crests which are relatively few in number. In the Elephantidae, the transverse crests (lamellae) are closer together, more numerous and spaces between them are filled with cementum. Most mastodonts were covered with hair.

Elephantidae

The last group of proboscideans arose in the Miocene from Stegolophodon, an animal with affinites to the mastodonts. Much of the early evolution occurred in Africa. The basic elephantine stock, Primelaphus, gave rise to three genera, Mammuthus, Elephas, and Loxodonta (Fig. 2).

The mammoths (Mammuthus) are the best known of the extinct elephants. Discoveries have been made of complete carcasses almost perfectly preserved in ice and frozen soil. These animals were highly evolved, in some respects more advanced than modern forms. They had closer affinites to Elephas than Loxodonta. Most members were adapted to grazing and lived on steppes and prairies. One of the largest members of the genus was the imperial mammoth (M. columbi) with a shoulder height of almost 4 metres compared with 3.5 metres for large African elephants. This species lived on the prairies of the southern United States and Mexico. The smaller woolly mammoth (M. primigenius) was about the size of the Asian elephant but had a number of adaptations for cold tundra steppes. The skin was thick and covered with long hair. The ears were small and large fat reserves were concentrated on the head and shoulders as well as large subcutaneous depots. The large tusks probably were used to sweep away snow exposing underlying vegetation.

Elephas recki dominates fossils of the African Pleistocene. While this species dominated the savannas, Loxodonta probably exploited forested habitats. With the extinction of Elephas, Loxodonta apparently invaded drier regions forming two subspecies, the forest elephant (Loxodonta africana cyclotis), and the bush elephant (L. a. africana).

http://www.deer.rr.ualberta.ca/library/phylogeny/Phylogeny.html#RTFToC23

===

Here's more about the elephant/manatee connection. Tres cool.:

http://www.abcnews.go.com/sections/science/DailyNews/elephants990511.html

===

Nice to have someone with a biology background here. Kazim and I were both physics majors, and I for one never took biology after high school.

Thanks! I've been following these boards for a while and have enjoyed reading you, Kazim, and others. I'm more of a chemist, actually, but I took a ton of biology/physiology classes in college. Now I'm back in grad school, plodding along again. : )

Amy

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Author: beckyz51 Big red star, 1000 posts Old School Fool Add to my Favorite Fools Ignore this person (you won't see their posts anymore) Number: 130 of 24987
Subject: Re: Self-Made Cells Date: 2/18/2001 7:31 AM
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Amy,
Now that you mention it, I could have used the wrong word, but Webster backs me up.Whew!
I said that I believe there is evolution within species (not to the point of becoming another species).
I just mean "change". And I'll use my husband's example-- the mighty Cockroach!
At some point the cockroach became a pest. So, man developed a chemical to kill it. All was well, until one day when they were back! They had somehow grown used to the chemical. Something 'changed'. But it was still a cockroach. And I think they've changed more than once to survive. YOU probably can tell me that 'young one'!
So, am I OK here, or do I need to change my word? I trust your judgement here, just keep it simple!
Becky

PS. I apologize to Chris, who told me where to go to find out how to cut and paste. I'll get there. But am anxious to post whenever I come up with an answer.

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Author: nf Big red star, 1000 posts Old School Fool Add to my Favorite Fools Ignore this person (you won't see their posts anymore) Number: 133 of 24987
Subject: Re: Self-Made Cells Date: 2/18/2001 11:00 PM
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Becky,

I said that I believe there is evolution within species (not to the point of becoming another
species).
I just mean "change". And I'll use my husband's example-- the mighty Cockroach!
At some point the cockroach became a pest. So, man developed a chemical to kill it. All was
well, until one day when they were back! They had somehow grown used to the chemical.
Something 'changed'. But it was still a cockroach. And I think they've changed more than once to
survive.


If you look at this example backwards you only killed
roaches that responded to the toxin in a favorable manner (death).Others may have become sick for a while,
some may (while eating) say hey this stuff ain't bad!Some others may say this stuff stinks!I'm otta here.

A realitive example would be peanuts.Near instant death to some people who mistakenly eat them.The smell can make some gravely ill.Most consider them good food.
And yes I understand instant death peanut people are in
the minority,but the point remains.

Chris




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Author: OldFatherHubbord Big red star, 1000 posts Old School Fool Add to my Favorite Fools Ignore this person (you won't see their posts anymore) Number: 159 of 24987
Subject: Re: Self-Made Cells Date: 2/20/2001 2:02 PM
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"poit"

It's not pretty,

DNA looks like flu mucus. :)sss

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Author: OldFatherHubbord Big red star, 1000 posts Old School Fool Add to my Favorite Fools Ignore this person (you won't see their posts anymore) Number: 160 of 24987
Subject: Re: Self-Made Cells Date: 2/20/2001 2:13 PM
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No, a pig and a hippo could not make a baby pippo.



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