<Annie> When I said "here" I meant your forum, not CG. I've been rummaging around CG most days, doing game info corrections, submitting correction slips, working on a couple of new game collections, etc...it's been "below the radar" stuff and I haven't been following that many discussions. I saw a mention of your birthday practically by accident.

BTW, good point about that emu - and the other large flightless birds - having chick-like heads. Hmmm.

<Benzol> Thx, no worries. I'm also very happy that cg started to open more editing options to you guys - these are good times. But you, and the rest of you editors, should remember to come up for some air every now and then! :D

<Tissue dispensers are to the left, folks. Let's just have a good cry about this and move on? Getting crowded on this bandwagon.>

<hms> thx. ;)

The plant has been sidelined since January after a tube break in a steam generator released traces of radiation.>

Now and then this occurs in water cooled nuclear reactors. Moreover, every few decades a Fukushima type of event is bound to happen. It's inevitable because of the nature of water at room temperatures. It can phase from liquid to gas, thus facilitating leaks and explosions. Furthermore if for any reason the coolant water supply us cut off permanently, a nuclear meltdown or explosion will inevitably occur. The lesson is that humanity should think of abandoning these intrinsically dangerous water cooled nuclear reactors, perhaps in favor of alternative carbon neutral energy sources and 4th generation nuclear plants. (More of this in <twinlark's> forum.)

These little accidents keep on releasing radionuclides into the environment, but the biosphere seems to be able to tolerate small amounts of radioactivity well. For me this is an interesting point. Background radiation is theorized to be one of the causes for evolution.

When Chernobyl exploded, nearly every mammal for kilometers around it died in a very specific way- thyroid failure. Uranium and plutonium fission produces large quantities of iodine 131, about 3% by weight. <http://en.wikipedia.org/wiki/Iodine...> Iodine 131 has important medical uses under controlled conditions, such as diagnostics and treatment of thyroid cancer and thyrotoxicosis, but if released in large amounts into the environment, it quickly concentrates in the thyroid glands of mammals destroying them.

What astonished a lot of observers is that after a few years, without humans around to hunt them, wild European mammals and birds underwent a population explosion in the Chernobyl Exclusion Zone (a 30 kilometer radius around the nuclear plant.) Many of these are rare endangered large mammals, including the wisent (European bison) and the introduced Przewalski's Horse. Since I-131 has a half life of only 8 days before decaying to stable Xenon-131, mammals apparently can re-enter the zone in relative safety after a few weeks.

Mutations caused by other radionuclides in the zone were at high rates, so how did the mammals survive in comparison to a theoretical human population inside the zone? I think the following factors are involved:

1. Wild mammals have higher reproductive rates than humans. Thus, even if harmful mutations kill a large percentage of their young, a lucky few that happened to have little or no harmful mutations would, without the competition of their siblings, readily survive into adulthood. Without an increased rate of mortality due to radiation, a percentage of young mammals always fail to survive intra-species competition and other natural causes. With increased mortality due to radiation, the percentage that fails to survive is mostly taken from the radiation-damaged cohort.

Think of it this way. A malicious entity always demands the sacrifice of half of the calves of a European bison population before age 1. A nuclear reactor spills its guts nearby and causes half of all newly birthed young to die of radiation poisoning and harmful mutations. The malicious entity sees its quota fulfilled and stops bothering the rest of the calves. Thus, whether or not the nuclear plant exploded, half of the wisent calves always tend to survive (or fail to).

<A natural nuclear fission reactor is a uranium deposit where self-sustaining nuclear chain reactions have occurred. This can be examined by analysis of isotope ratios. The existence of this phenomenon was discovered in 1972 at Oklo in Gabon, Africa, by French physicist Francis Perrin. The conditions under which a natural nuclear reactor could exist had been predicted in 1956 by Paul Kazuo Kuroda.[1] The conditions found were very similar to what was predicted.

Oklo is the only known location for this in the world and consists of 16 sites at which self-sustaining nuclear fission reactions took place approximately 1.7 billion years ago, and ran for a few hundred thousand years, averaging 100 kW of power output during that time...

A key factor that made the reaction possible was that, at the time the reactor went critical 1.7 billion years ago, the fissile isotope 235U made up about 3.1% of the natural uranium, which is comparable to the amount used in some of today's reactors. (The remaining 97% was non-fissile 238U.) Because 235U has a shorter half life than 238U, and thus decays more rapidly, the current abundance of 235U in natural uranium is about 0.7%. A natural nuclear reactor is therefore no longer possible on Earth without heavy water or graphite.>

http://en.wikipedia.org/wiki/Natura...

Not only was Uranium-235 more abundant 2 billion years ago, so was every other primordial radionuclide. Even in the Triassic period when mammals first evolved 250 to 200 million years ago, the Earth was much more radioactive than it is today.

For instance, Plutonium-244 is regarded as the rarest naturally occurring radionuclide. With a half-life of 80 million years, given the Earth's age of about 4.5 billion years or about 50 Plutonium-244 half-lives, Pl-244 exists today in just barely detectable quantities in the environment.

However, during the Triassic, three of its half-lives away in time, it must have existed in y times y times y quantities if it exists in y quantities now.

Our mammalian ancestors in the Triassic, and more so their Synapsid predecessors in the Carboniferous period 300 million years ago, must have been exposed to more background environmental radiation.

Pure luck:
<SETTLEMENT DATE: Jul-31-12
PROJECTED PAYOUT: 3,032 (60:1)
Biel Rd 8: PICK THREE
Black-White-Black
YOU WIN! COLLECT 3032 50c$
[cash in ticket]>

And yes, I've been following your posts in <twinlark>'s forum too.

<Mark> I have sharks for breakfast! ;)

<(1) Annie K. 5,510>

<Hanh> yes, it's the same picture. I originally just picked my avatar out of the available pool here, but I'm very attached to it now. :)

<L E A D E R B O A R D
updated Thu Aug 2, 05:30
User Net Worth

And good luck with further investigations/inevestments :)