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I have a theory.........

rainbowsrus Oct 01, 2007 09:02 PM

Well, I finished sexing all my babies tonight and had a very interesting observation. I've had four litters, not listed in order:

34 eggs 1 still, 1 pair twins, 34 live babies
17 eggs 1 still, 16 live babies
32 eggs 2 still, 16 slugs, 13 live babies (includes the one with the odd eye)
?? eggs 15 live babies, I believe Wilma ate up all the slugs as I didn't find this litter as soon and she was clearly coming back out from having gone back in to the nest box after leaving at least once before. Head and tail outside nest bbox, babies all inside nest box. Also she looked like she had had a meal just like Betty who I saw eat 16 slugs.

Both litters that had no slugs had a mix of babies. 17.17 and 10.06 More or less an expected outcome from the=at many babies and the 10.06 while not even would easily be within some level of standard deviation.

Both litters where there were slugs (one visually verified and one surmised) Were predominantly female. 3.12 and 0.13

Makes you go hmmmmmmmmm...?????

I'm thinking there may have been two affects of my cooler temps.

1) Slowed the "incubation rate" inside mom and thereby caused longer gestation times from those posted by Mike. Already discussed and I believe agreed upon as probable.

2) Significantly reduced the survival rate on male embryos. ie many of those embryos that were male simply did not survive to develop into little snakes and came out as slugs.

All four females were kept at the same temperatures but maybe two were better at thermoregulating then the other two. Also the other two Wilma and Betty came to me last year as established already been bred adult females and coule have gone through a climatic change from their prior keeper. Note to self, check with Haward on his temp settings as he remembers them.

Bottom line is I'm sitting sweet and pretty on 30.48 babies

Was really wierd sexing them, I started wth Bullseyes litter and got 17.17 then proceeded to sex Betty and Wilma's litters and out of their 28 babies only found three males. Had I not just sexed Bullseyes litter I woulda thought I was doing it wrong. (was still second guessing but each time I went back to a male from bullseyes litter I was able to verify it as a male np). Then to cap it off, I sexed Savannah's litter and found males left and right, more males than females 10.6 in the end.

I d love to hear any and all thoughts on the subject......
-----
Thanks,

Dave Colling

www.rainbows-r-us-reptiles.com

0.1 Wife (WC and still very fiesty)
0.2 kids (CBB, a big part of our selective breeding program)

LOL, to many snakes to list, last count:
24.36 BRB
19.19 BCI
And those are only the breeders

lots.lots.lots feeder mice and rats

Replies (32)

natsamjosh Oct 01, 2007 09:30 PM

All that just to prove that men are slugs?

Seriously, it sounds very plausible to me, but I have no
experience to provide supporting evidence.

Very interesting topic!
-----
------
Thanks,
Ed

Railrider1920 Oct 01, 2007 09:44 PM

>>All that just to prove that men are slugs?
>>
>>Seriously, it sounds very plausible to me, but I have no
>>experience to provide supporting evidence.
>>
>>Very interesting topic!
>>-----
>>------
>>Thanks,
>>Ed
-----
For Sale cheap: One (1) 6' 19 yr old male. Does no house work. Has no job and will complain. Constantly.
0.1 Brazilian Rainbow Boa-Ziggy
1.0 Creamscicle motley corn--Cozmo
0.1 Creamscicle corn--Wanda
0.0.1 Normal corn
0.1 Black Pine - Spazz
1.0 Eastern King-Ozy
1.0 Bearded Dragon - Gomer

rainbowsrus Oct 02, 2007 10:24 AM

No you don't get it,

all that to prove it's not "our fault" we are slugs!!!!
-----
Thanks,

Dave Colling

www.rainbows-r-us-reptiles.com

0.1 Wife (WC and still very fiesty)
0.2 kids (CBB, a big part of our selective breeding program)

LOL, to many snakes to list, last count:
24.36 BRB
19.19 BCI
And those are only the breeders

lots.lots.lots feeder mice and rats

run26neys Oct 01, 2007 09:35 PM

I know from tv that the sex of crocidiles is determined by incubation temps, and the females will be in the bottom of the nest where it is warmer. This also protects the females from preditors as the male eggs cover them. Females are more important for species survival and this is how crocs have evloved.

It is interesting that the numbers are so different for the litters with slugs.
-----
Mike

6.7 BRB
1.2 Spotted Python
1.0 Cal. King

Jeff Clark Oct 02, 2007 07:38 AM

Dave,
...I am just home from work and dead tired and trying to figure this out as it compares to my litters. The first thing that comes to mind is that in many recent years I have had lots of slugs and the babies have been female heavy. This year much fewer slugs but my litters are very male heavy.
Jeff

>>Well, I finished sexing all my babies tonight and had a very interesting observation. I've had four litters, not listed in order:
>>
>>34 eggs 1 still, 1 pair twins, 34 live babies
>>17 eggs 1 still, 16 live babies
>>32 eggs 2 still, 16 slugs, 13 live babies (includes the one with the odd eye)
>>?? eggs 15 live babies, I believe Wilma ate up all the slugs as I didn't find this litter as soon and she was clearly coming back out from having gone back in to the nest box after leaving at least once before. Head and tail outside nest bbox, babies all inside nest box. Also she looked like she had had a meal just like Betty who I saw eat 16 slugs.
>>
>>Both litters that had no slugs had a mix of babies. 17.17 and 10.06 More or less an expected outcome from the=at many babies and the 10.06 while not even would easily be within some level of standard deviation.
>>
>>Both litters where there were slugs (one visually verified and one surmised) Were predominantly female. 3.12 and 0.13
>>
>>Makes you go hmmmmmmmmm...?????
>>
>>I'm thinking there may have been two affects of my cooler temps.
>>
>>1) Slowed the "incubation rate" inside mom and thereby caused longer gestation times from those posted by Mike. Already discussed and I believe agreed upon as probable.
>>
>>2) Significantly reduced the survival rate on male embryos. ie many of those embryos that were male simply did not survive to develop into little snakes and came out as slugs.
>>
>>
>>
>>All four females were kept at the same temperatures but maybe two were better at thermoregulating then the other two. Also the other two Wilma and Betty came to me last year as established already been bred adult females and coule have gone through a climatic change from their prior keeper. Note to self, check with Haward on his temp settings as he remembers them.
>>
>>
>>Bottom line is I'm sitting sweet and pretty on 30.48 babies
>>
>>Was really wierd sexing them, I started wth Bullseyes litter and got 17.17 then proceeded to sex Betty and Wilma's litters and out of their 28 babies only found three males. Had I not just sexed Bullseyes litter I woulda thought I was doing it wrong. (was still second guessing but each time I went back to a male from bullseyes litter I was able to verify it as a male np). Then to cap it off, I sexed Savannah's litter and found males left and right, more males than females 10.6 in the end.
>>
>>
>>I d love to hear any and all thoughts on the subject......
>>-----
>>Thanks,
>>
>>
>>Dave Colling
>>
>>www.rainbows-r-us-reptiles.com
>>
>>
>>
>>0.1 Wife (WC and still very fiesty)
>>0.2 kids (CBB, a big part of our selective breeding program)
>>
>>LOL, to many snakes to list, last count:
>>24.36 BRB
>>19.19 BCI
>>And those are only the breeders
>>
>>lots.lots.lots feeder mice and rats

rainbowsrus Oct 02, 2007 10:32 AM

Jeff, Thanks, that does seem to fit into the "slugs are predominantly male" theory. Can you supply any temp info to go with that?

Brings to mind another thought, in warmer periods wouldn't food (and predators) be available in higher numbers? And in cooler periods wouldn't food (and predators) be fewer? Evolutionary baby adjustment ratio.... when food is plentiful more babies born. When food is less plentiful, fewer babies?

Making population adjustments to baby males would have a smaller affect on future propogation of the species.
-----
Thanks,

Dave Colling

www.rainbows-r-us-reptiles.com

0.1 Wife (WC and still very fiesty)
0.2 kids (CBB, a big part of our selective breeding program)

LOL, to many snakes to list, last count:
24.36 BRB
19.19 BCI
And those are only the breeders

lots.lots.lots feeder mice and rats

run26neys Oct 02, 2007 02:23 PM

Dave, Jeff's comments fit your therory. He is male heavy this year and has had fewer slugs this year too.
-----
Mike

6.7 BRB
1.2 Spotted Python
1.0 Cal. King

rainbowsrus Oct 02, 2007 02:29 PM

Couch potatoe males?
-----
Thanks,

Dave Colling

www.rainbows-r-us-reptiles.com

0.1 Wife (WC and still very fiesty)
0.2 kids (CBB, a big part of our selective breeding program)

LOL, to many snakes to list, last count:
24.36 BRB
19.19 BCI
And those are only the breeders

lots.lots.lots feeder mice and rats

run26neys Oct 02, 2007 03:17 PM

I guess so...

I think it makes sense that the majority of the slugs are male. Females are more important for species survival and something must cause the males to become slugs before the females do.
-----
Mike

6.7 BRB
1.2 Spotted Python
1.0 Cal. King

waspinator421 Oct 02, 2007 04:04 PM

I am confused... I thought slugs were just unfertilized eggs?
-----
Aubrey Ross

©
www.SlipstreamSerpents.com

rainbowsrus Oct 02, 2007 04:39 PM

A monor point in semantics.... Slugs are ovum that never developed into viable offspring. Not necessarily ones that never gor fertilized. Could some be fertilized and then "die" before developing into baby snakes??
-----
Thanks,

Dave Colling

www.rainbows-r-us-reptiles.com

0.1 Wife (WC and still very fiesty)
0.2 kids (CBB, a big part of our selective breeding program)

LOL, to many snakes to list, last count:
24.36 BRB
19.19 BCI
And those are only the breeders

lots.lots.lots feeder mice and rats

Jeff Clark Oct 02, 2007 05:49 PM

At my house every slug gets looked at very closely. In the past every snake that died gravid also got opened up for a look. Our failures can teach us something. What I have found looking at slugs is that most of them do not have any identifiable fetal structures but a few do have spots that probably indicate an egg that got fertilized but died ealy in development. In a few rare cases I have found identifiable dead baby snakes between 3 and 12 inches long. When I bred egg layers I opened every bad egg and dozens of good ones trying to learn something from them.
Jeff

>>A monor point in semantics.... Slugs are ovum that never developed into viable offspring. Not necessarily ones that never gor fertilized. Could some be fertilized and then "die" before developing into baby snakes??
>>-----
>>Thanks,
>>
>>
>>Dave Colling
>>
>>www.rainbows-r-us-reptiles.com
>>
>>
>>
>>0.1 Wife (WC and still very fiesty)
>>0.2 kids (CBB, a big part of our selective breeding program)
>>
>>LOL, to many snakes to list, last count:
>>24.36 BRB
>>19.19 BCI
>>And those are only the breeders
>>
>>lots.lots.lots feeder mice and rats

natsamjosh Oct 02, 2007 07:21 PM

...if we all chip in to buy a powerful enough microscope,
could we see a slug cell's chromosomes to determine its sex??
I'll throw in a few bucks in the name of science.

>>At my house every slug gets looked at very closely. In the past every snake that died gravid also got opened up for a look. Our failures can teach us something. What I have found looking at slugs is that most of them do not have any identifiable fetal structures but a few do have spots that probably indicate an egg that got fertilized but died ealy in development. In a few rare cases I have found identifiable dead baby snakes between 3 and 12 inches long. When I bred egg layers I opened every bad egg and dozens of good ones trying to learn something from them.
>>Jeff
>>
>>>>A monor point in semantics.... Slugs are ovum that never developed into viable offspring. Not necessarily ones that never gor fertilized. Could some be fertilized and then "die" before developing into baby snakes??
>>>>-----
>>>>Thanks,
>>>>
>>>>
>>>>Dave Colling
>>>>
>>>>www.rainbows-r-us-reptiles.com
>>>>
>>>>
>>>>
>>>>0.1 Wife (WC and still very fiesty)
>>>>0.2 kids (CBB, a big part of our selective breeding program)
>>>>
>>>>LOL, to many snakes to list, last count:
>>>>24.36 BRB
>>>>19.19 BCI
>>>>And those are only the breeders
>>>>
>>>>lots.lots.lots feeder mice and rats
-----
------
Thanks,
Ed

strictly4fun Oct 02, 2007 10:31 PM

happy I'll throw in a few bucks too

natsamjosh Oct 03, 2007 11:17 AM

I knew I can count on you, Bob! You can send the electron micrsocope to me whenever convenient.

>>happy I'll throw in a few bucks too
-----
------
Thanks,
Ed

natsamjosh Oct 02, 2007 04:11 PM

As fascinating as I find this topic, you guys do realize the
female members of this forum are laughing their a--es off
at us. Maybe we should discuss it offline...

>>I guess so...
>>
>>I think it makes sense that the majority of the slugs are male. Females are more important for species survival and something must cause the males to become slugs before the females do.
>>-----
>>Mike
>>
>>6.7 BRB
>>1.2 Spotted Python
>>1.0 Cal. King
-----
------
Thanks,
Ed

rainbowsrus Oct 02, 2007 04:37 PM

Hey, I'm willing to laugh at anything that is funny, including my entire gender!!!!!
-----
Thanks,

Dave Colling

www.rainbows-r-us-reptiles.com

0.1 Wife (WC and still very fiesty)
0.2 kids (CBB, a big part of our selective breeding program)

LOL, to many snakes to list, last count:
24.36 BRB
19.19 BCI
And those are only the breeders

lots.lots.lots feeder mice and rats

tim21087 Oct 02, 2007 08:28 AM

I have heard that warmer temps cause more female births in reptiles. But cooler temps cause males not dead males :/ And if the temps were too cold you would think that it would affect all the babies and not just the male embryos. I don't have anything to back this up with, as I'm not a breeder but, I don't see how cooler temps would only kill male babies.
-----
Thank you,

Tim

0.1 wc girlfriend- Melissa (still very feisty even after a year and a half of loving care )
0.1 CRB- Tempest
0.1 JCP- Serenity
1.0 Black Cat- Chester A Arthur

superdave1781 Oct 02, 2007 09:31 AM

I thought it was the other way around, that cooler temps produced more females, and warmer temps produced more males...maybe it's one way with certain reptiles/snakes, and the other way with other reptiles/snakes. That doesn't seem to be what caused the extreme contrast that Dave got since all were kept at the same temp. Where they all mated to the same male? Where any of the females from the same bloodline? It might be something genetic with either the male(s) or female(s) if it occurs every season.
-----
-David

Check out my pet pics at:
http://www.myspace.com/obx_fisherman

1.0 ball python (Pandora - don't ask)
1.0 argentine boa (Prometheus)
0.1 hogg island boa (Andromeda)
0.0.1 brazilian rainbow boa (Inara)
1.0 kenyan sand boa (Diablo)
1.0 normal corn snake(Cypress)
0.1 amery. corn snake (Morgan LaFay)
0.0.2 baby corns (Romulus and Remus)
- 1 normal, 1 ghost
0.0.1 banded cali. kingsnake (Cain)
1.0 tangerine honduran milksnake (Narcissus)
0.0.1 snow corn snake (Valkyrie)
1.0 amazon tree boa (Pegasus)
1.0 colombian boa (Poseidon)
0.1 albino san diego gopher snake (Athena)
0.0.1 sandfish skink (Slick)
0.0.1 fire skink (Phoenix)
1.0 dog (Luke)

the wife's pets:
1.0 bearded dragon (Leonidas)
1.1 ferrets (Ares, Enyo)
0.0.1 betta fish (Captain Morgan)
1.2 cats (Galahad, Ripley and Sassy)
0.1 Boxer

rainbowsrus Oct 02, 2007 10:42 AM

The two groups are completely unrelated. The one trio Fred/Wilma/Betty came from Howard Leong as his adult breeders. All the rest of my collection came from other sources including Bullseye being produced by me in 2001.

Definately not sure if temps had anything to do with it but very curious how both litters with lots of slugs had high female ratios while both litters with no slugs were even or male heavy.

Both males with higher male baby ratios were new first time breeders. The one male, Fred, for both female heavy litters is an older unknown age male. Could it be he's shooting weak male sperm? But if that were the case, then wouldn't the eggs be fertilized by more female sperm? Millions of sperm, few eggs.... From the numbers I'm thinking that most of the eggs that were fertilized by male sperm did not survive for some reason.
-----
Thanks,

Dave Colling

www.rainbows-r-us-reptiles.com

0.1 Wife (WC and still very fiesty)
0.2 kids (CBB, a big part of our selective breeding program)

LOL, to many snakes to list, last count:
24.36 BRB
19.19 BCI
And those are only the breeders

lots.lots.lots feeder mice and rats

superdave1781 Oct 02, 2007 12:38 PM

yeah, I agree...something caused the male eggs to fail. If I understood you right, both litters with a high number of slugs and mostly females were produced by the same, older male. He seems to be the common variable. Have you breed him before? Have you had this happen in past years?
-----
-David

Check out my pet pics at:
http://www.myspace.com/obx_fisherman

1.0 ball python (Pandora - don't ask)
1.0 argentine boa (Prometheus)
0.1 hogg island boa (Andromeda)
0.0.1 brazilian rainbow boa (Inara)
1.0 kenyan sand boa (Diablo)
1.0 normal corn snake(Cypress)
0.1 amery. corn snake (Morgan LaFay)
0.0.2 baby corns (Romulus and Remus)
- 1 normal, 1 ghost
0.0.1 banded cali. kingsnake (Cain)
1.0 tangerine honduran milksnake (Narcissus)
0.0.1 snow corn snake (Valkyrie)
1.0 amazon tree boa (Pegasus)
1.0 colombian boa (Poseidon)
0.1 albino san diego gopher snake (Athena)
0.0.1 sandfish skink (Slick)
0.0.1 fire skink (Phoenix)
1.0 dog (Luke)

the wife's pets:
1.0 bearded dragon (Leonidas)
1.1 ferrets (Ares, Enyo)
0.0.1 betta fish (Captain Morgan)
1.2 cats (Galahad, Ripley and Sassy)
0.1 Boxer

rainbowsrus Oct 02, 2007 01:04 PM

This is my first year with him so no prior data!

I've also upgraded my heating and control systems so can maintain reasonably precise temps now, so can't compare old data in true apples to apples form.
-----
Thanks,

Dave Colling

www.rainbows-r-us-reptiles.com

0.1 Wife (WC and still very fiesty)
0.2 kids (CBB, a big part of our selective breeding program)

LOL, to many snakes to list, last count:
24.36 BRB
19.19 BCI
And those are only the breeders

lots.lots.lots feeder mice and rats

tim21087 Oct 02, 2007 04:03 PM

I could be wrong I was just remembering what I had heard off the top of my heard. It is very plausible that I just remember it backwards. Either way I don't think it was genetic from the parents but I have no proof to back up my thoughts I just don't feel that sex can be passed like that.
-----
Thank you,

Tim

0.1 wc girlfriend- Melissa (still very feisty even after a year and a half of loving care )
0.1 CRB- Tempest
0.1 JCP- Serenity
1.0 Black Cat- Chester A Arthur

superdave1781 Oct 02, 2007 10:06 PM

well, I definitely could be wrong too, as I also was speaking by what I remembered off the top of my head! About being genetic, that was just a guess based on the info. Unfortunately, we don't have years of data and/or a vast number of results to come to a reliable conclusion. It could just be coincidence that the two females fertilized by the same male both had many slugs and mostly female babies. At the same time, it could be genetics...maybe the females he helped create are high maintenance women and sucked the males dry before they were even born jk
-----
-David

Check out my pet pics at:
http://www.myspace.com/obx_fisherman

1.0 ball python (Pandora - don't ask)
1.0 argentine boa (Prometheus)
0.1 hogg island boa (Andromeda)
0.0.1 brazilian rainbow boa (Inara)
1.0 kenyan sand boa (Diablo)
1.0 normal corn snake(Cypress)
0.1 amery. corn snake (Morgan LaFay)
0.0.2 baby corns (Romulus and Remus)
- 1 normal, 1 ghost
0.0.1 banded cali. kingsnake (Cain)
1.0 tangerine honduran milksnake (Narcissus)
0.0.1 snow corn snake (Valkyrie)
1.0 amazon tree boa (Pegasus)
1.0 colombian boa (Poseidon)
0.1 albino san diego gopher snake (Athena)
0.0.1 sandfish skink (Slick)
0.0.1 fire skink (Phoenix)
1.0 dog (Luke)

the wife's pets:
1.0 bearded dragon (Leonidas)
1.1 ferrets (Ares, Enyo)
0.0.1 betta fish (Captain Morgan)
1.2 cats (Galahad, Ripley and Sassy)
0.1 Boxer

tim21087 Oct 03, 2007 08:25 AM

"maybe the females he helped create are high maintenance women and sucked the males dry before they were even born jk"

Hahahaha that's great. One of the funniest things I've read in a while. But as far as your point goes you are completely correct on the lacking sound data. I wish it could be proved one way or the other cause that would be a huge finding. But sadly until someone gets a huge research grant for for a study on this subject it'll never happen because it's just so time and money consuming.
-----
Thank you,

Tim

0.1 wc girlfriend- Melissa (still very feisty even after a year and a half of loving care )
0.1 CRB- Tempest
0.1 JCP- Serenity
1.0 Black Cat- Chester A Arthur

natsamjosh Oct 02, 2007 11:06 AM

Interesting article:

http://www.sciam.com/article.cfm?articleID=000D604B-9F27-1C60-B882809EC588ED9F
-----
------
Thanks,
Ed

rainbowsrus Oct 02, 2007 11:11 AM

Way cool, wonder if the litter size is affected as well?
-----
Thanks,

Dave Colling

www.rainbows-r-us-reptiles.com

0.1 Wife (WC and still very fiesty)
0.2 kids (CBB, a big part of our selective breeding program)

LOL, to many snakes to list, last count:
24.36 BRB
19.19 BCI
And those are only the breeders

lots.lots.lots feeder mice and rats

natsamjosh Oct 02, 2007 11:16 AM

Great question. This is also pretty cool:

http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/S/SexChromosomes.html

"In some cases (e.g. many turtles and lizards), a higher temperature during incubation favors the production of females.
In other cases (e.g., alligators), a higher temperature favors the production of males."

I need to try to digest all this stuff, but right now I need to
go digest some lunch!

>>Way cool, wonder if the litter size is affected as well?
>>-----
>>Thanks,
>>
>>
>>Dave Colling
>>
>>www.rainbows-r-us-reptiles.com
>>
>>
>>
>>0.1 Wife (WC and still very fiesty)
>>0.2 kids (CBB, a big part of our selective breeding program)
>>
>>LOL, to many snakes to list, last count:
>>24.36 BRB
>>19.19 BCI
>>And those are only the breeders
>>
>>lots.lots.lots feeder mice and rats
-----
------
Thanks,
Ed

Jeff Clark Oct 02, 2007 05:39 PM

Ed,
..That link is interesting. I think a very important point for us to consider from the article is:

"The choice is usually determined by the temperature at which early embryonic development takes place."

That word "early" seems pretty important to me. We really do not know if fertilization is taking place very soon after mating in which case we may have relatively cool temperatures because we may still have the adults in cooling or if actual fertilization takes place quite some time after mating in which case most of our breeders are warmed back up. I do think it is possible that sex determination in BRBs could be temperare dependent but our control of temperatures and more specifically temperatures at the precise time of fertilization are not well enough controlled to say for sure. We can all set out thermostats on the exact same temperature but the variances due to cage size and furnishings and room temperature and heater type and location can all greatly effect the temperature that one specific snake selects in it's cage. A cage may contain dozens of different "mini" environements. Just a simple temperature gradient across a very plain cage with no furniture allows a snake to select from an infinite number of locations that each have very slightly different temperature.
Jeff

natsamjosh Oct 03, 2007 03:27 PM

Hey Jeff,

Yeah, that is an interesting article. I had a chance to read it more closely (and look up some other stuff), and not that it makes it easier in the end to prove or disprove, but I'm thinking the fertilization might be irrelevant. Here's my reasoning. First, the quote about embryonic development was qualified as applying to only "some snakes." Secondly, from what I read, boas do have sex chromosomes, and oddly enough they work oppositely of the way the do for mammals. In mammals, the male's sex chromosome contribution (X or Y) will determine the sex of the offspring. Females have two X's. In boas, however, the males have the two of the same sex chromosomes (ZZ), and the females have the pair that's different (ZW). So if I'm thinking this through correctly, the female's contribution to it's egg (either Z for male or W for female) will determine the sex of the baby; so time of fertilization may not even be relevant, at least as far as determining what gender the baby is. The egg has already determined the gender.

So let me toss out another hypothesis. The temperature at the time the female creates the egg might effect which sex chromosome (W or Z) get passed on, thereby pre-determining, if you will, the sex of a future embryo. Or could be some other factor other than temperature. Or could be random, I suppose.

Regarding the cause of the slugs, as Superdave astutely pointed out, maybe one cause of Dave's scenario was a defective sex chromosome of the father. That could, on average, be passed on to 50% of the embryos, which seems to be about what Dave saw with his litters.

When you get slugs, do you normally see a roughly 1:1 ratio of slugs to developed babies?

So what Dave saw might be a combination of temperature (which would skew the gender ratio) and a male with a defective chromosome (which would cause about 50% slugs? Anyway, just more speculation for discussion, if anyone is even interested. Obviously we would need more data points/slug litters to figure
things out further.

When Bob scrapes up enough money for the microscope, we can start looking at the slug chromosomes to see if they are mostly/all males.

>>Ed,
>>..That link is interesting. I think a very important point for us to consider from the article is:
>>
>>"The choice is usually determined by the temperature at which early embryonic development takes place."
>>
>>That word "early" seems pretty important to me. We really do not know if fertilization is taking place very soon after mating in which case we may have relatively cool temperatures because we may still have the adults in cooling or if actual fertilization takes place quite some time after mating in which case most of our breeders are warmed back up. I do think it is possible that sex determination in BRBs could be temperare dependent but our control of temperatures and more specifically temperatures at the precise time of fertilization are not well enough controlled to say for sure. We can all set out thermostats on the exact same temperature but the variances due to cage size and furnishings and room temperature and heater type and location can all greatly effect the temperature that one specific snake selects in it's cage. A cage may contain dozens of different "mini" environements. Just a simple temperature gradient across a very plain cage with no furniture allows a snake to select from an infinite number of locations that each have very slightly different temperature.
>>Jeff
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Thanks,
Ed

strictly4fun Oct 03, 2007 07:10 PM

calico project and get some money for it, will we have enough for a electron microscope at least I think it was an electron microscope but I do know that this thread is getting hard to keep up with so I need to go back to school and learn some more before I talk to you again Edlol
Bob

natsamjosh Oct 03, 2007 08:40 PM

Shoot, with that calico we might be able to get a few microscopes and also maybe dinner at Burger King!

Sorry if I was long winded, basically what I was trying to say is that the female's egg could determines the sex of the offspring. The male's sperm/fertilization may not be a factor in determining gender of the baby. (See above post about chickens.)

What's fascinating to me is that it is the opposite with mammals! While we may be slugs, at least we have some input in what gender our children turn out to be.

>>calico project and get some money for it, will we have enough for a electron microscope at least I think it was an electron microscope but I do know that this thread is getting hard to keep up with so I need to go back to school and learn some more before I talk to you again Edlol
>>Bob

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Thanks,
Ed

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