Sex determination in Varanids?

[crocdoc]

Originally Posted by smy_749

If he had done this with 3 or 4 juvies, and consistently only received one male, and under the same incubation controls, raised another group of babies, each alone in isolation, and received the expected 50/50 ratio, then maybe you could look into it.

You'd have to do this x several hundred times for it to be statistically significant.

There are a lot of really interesting books (Irrationality, The Invisible Gorilla etc) on perception, memory and the distortion of reality that are worth reading. We remember coincidences because they surprise us, but end up reading a lot more into them than we should. We remember the time we walked down to the shop at just the right time to bump into an old friend we hadn't seen in years, but forget the other 364 times we walked down there that year without bumping into anyone at all.

The general public has a particularly poor understanding of the statistics of averages nor what 'random' really means. For example, if the average number of fatal shark attacks in a particular year is around 1 and suddenly there's a year during which 4 people get killed, everyone (including the media) immediately assumes that sharks are increasing in number at a rapid rate. No one stops to think that sharks can't grow to man-eater size in a single year, quickly enough to bolster the number of man-eaters by 400% from one year to the next.

[infernalis]

Originally Posted by crocdoc

The general public has a particularly poor understanding of the statistics of averages nor what 'random' really means. For example, if the average number of fatal shark attacks in a particular year is around 1 and suddenly there's a year during which 4 people get killed, everyone (including the media) immediately assumes that sharks are increasing in number at a rapid rate. No one stops to think that sharks can't grow to man-eater size in a single year, quickly enough to bolster the number of man-eaters by 400% from one year to the next.

Yes, I see this every day, on MANY subjects.

[smy_749]

Yea I agree about the several hundred thing, even if it shows up as a 1.2 trio but you've only tested it 10 or 20 times, you still haven't ruled out coincidence or other factors. Thats why I said you could look into it, not "you have discredited all science with your breakthrough research techniques based on opinion and sound intellect"

I'm not big on statistics honestly, I'm aware they play a huge role in science, but people just play with them too often for some other agenda. 1 Shark a year, thats not so bad, pretty safe *goes swimming*. When in reality it could be a pattern where every few years they migrate to that area and eat 20 tourists, and the in between years are 0 occurrences.

P.S. The earth is flat.

[crocdoc]

Originally Posted by smy_749

I'm not big on statistics honestly, I'm aware they play a huge role in science, but people just play with them too often for some other agenda.

Well, you can't really play with proper statistics, but it is easy to play with people's misconceptions of statistics and that is what people with an agenda do.

Originally Posted by smy_749

1 Shark a year, thats not so bad, pretty safe *goes swimming*. When in reality it could be a pattern where every few years they migrate to that area and eat 20 tourists, and the in between years are 0 occurrences.

Well, except that the 1 fatal attack per year stat is for a whole country, which is completely surrounded by water (Australia) so that's a strange migration (from elsewhere to a whole country, or even to the southern half of a country since most of the shark attacks are in cooler water). You'd also be suggesting a random migration pattern, in which large numbers of sharks get together and migrate every few years, but the number of years in between these migrations is random. That would be highly unlikely for a biological system.

See? Earth is round again.


,

[smy_749]

I agree, although you can use statistics which have no relevance because you didn't have any controls. There was a study about eating icecream causes Polio in the united states because the statistics said that both polio and icecream sales increased in the summer time, so polio must be caused by icecream. Or maybe that just proves your point of using them incorrectly, I don't know but its still funny.

Also about the shark thing, I forgot you live in australia. I don't know much about sharks but from watching enough discovery channel stuff, I know that a few species around the continental U.S. do migrate, where and for what reason I'm not sure. Also I didn't mean random, I just meant perhaps they come back every certain number of years for something (maybe to breed like salmon, or sea turtles or whatever). I need to brush up on my shark knowledge I guess :-P.

I just thought of a better example, because it was happening miami beach or something. A group of sharks which normally shows up on the shore earlier in the spring, before tourists start piling in for spring break, showed up during spring break this year due to changes in weather patterns. So maybe random weather events (which are likely unlike random biological) could cause this.

[crocdoc]

Originally Posted by smy_749

Or maybe that just proves your point of using them incorrectly

Bingo. That was exactly my point. The abuse of statistics, such as somebody trying to make a correlation between two unrelated (but perhaps, individually, perfectly legit statistics) doesn't make the statistics themselves bad. That's a Kent Hovind favourite trick, combining unrelated stats to tell a fable. It works on the mathematically dim. One of my favourites (done in jest) is on venganza.org, relating to the inverse relationship between global warming and piracy (if you're keen, go to venganza.org, click on About and then click the link to the open letter to the Kansas School Board and scroll down).

Regarding the shark thing, your spring break example was in reference to a known event that had been moved because of weather. Consequently, being a known occurrence the change in timing was recognised as such (which is how you were able to read about it).

I know what you were getting at - perhaps there's a pattern here in Australia that we haven't identified as of yet. Not in this instance, for the pattern would have to be random. People have been keeping stats on shark attacks, so graphs are readily available. The public tends to concentrate on the tiny peaks from one year to the next, but forget the big picture (loads of little peaks and troughs which, when one stands far enough away, shows up as a pretty straight line). Keep in mind that the numbers we are talking about are very low. One fatality for a population of 30 million per year is an incredibly small percentage so there's a fair bit of 'play' before changes start approaching significance.

[smy_749]

understood.
You guys only have 30 million? Is it hard for people to get permanent residence in australia, thats a serious question...or even a visitor visa?

[infernalis]

Not to distract too much, but skewing statistics is a government favourite here.

Millions upon millions of law abiding people own guns, but one nut case every half decade, the government makes it sound like a war zone.

[murrindindi]

Originally Posted by smy_749

understood.
You guys only have 30 million? Is it hard for people to get permanent residence in australia, thats a serious question...or even a visitor visa?

Hi, it`s not hard to get a visitor`s visa, much more dificult to get permanent residence (certain age range, occupation, minimum ammount of money, etc). Is it worth trying for the latter? You bet it is!!!!
So when are you planning on going (at least for a holiday)?

[smy_749]

Originally Posted by murrindindi

Hi, it`s not hard to get a visitor`s visa, much more dificult to get permanent residence (certain age range, occupation, minimum ammount of money, etc). Is it worth trying for the latter? You bet it is!!!!
So when are you planning on going (at least for a holiday)?

When I finish school, and save a bit of money. Probably in the winter, which would be your summer right?

[murrindindi]

Originally Posted by smy_749

When I finish school, and save a bit of money. Probably in the winter, which would be your summer right?

In the temperate states our summer is from november to february (here in England, it`s one or two days every few years)..... (Or so I`m told, I`ve haven`t noticed it yet)...

[infernalis]

Originally Posted by murrindindi

Hi, it`s not hard to get a visitor`s visa, much more dificult to get permanent residence (certain age range, occupation, minimum ammount of money, etc). Is it worth trying for the latter? You bet it is!!!!
So when are you planning on going (at least for a holiday)?

Gee, only a couple hundred years ago, all one had to do is commit a crime to get permanent residence.

[murrindindi]

Originally Posted by murrindindi

In the temperate states our summer is from november to february (here in England, it`s one or two days every few years)..... (Or so I`m told, I`ve haven`t noticed it yet)...

Silly me, november is still spring, let`s try DECEMBER is the start of summer (it felt like summer when I went home last november, that`s what caused the mistake)....

[smy_749]

Originally Posted by murrindindi

Silly me, november is still spring, let`s try DECEMBER is the start of summer (it felt like summer when I went home last november, that`s what caused the mistake)....

I'm confused, are you australian living in australia or...I thought i read that you were living in England or something.

[murrindindi]

Originally Posted by smy_749

I'm confused, are you australian living in australia or...I thought i read that you were living in England or something.

In spite of not knowing when summer starts, I was born near Perth, W.A, grew up in Melbourne, Victoria, but have been living here in the U.K for some years which means I`m still an Aussie and always will be!
I have some family here, which is why I am still here (it`s o.k, but not really "home").