5 ms·

Temperature based sex determination was new to me, so I went searching for more information. This book chapter describes the mechanism: https://www.ncbi.nlm.ni

by new299 4y ago

Temperature based sex determination was new to me, so I went searching for more information. This book chapter describes the mechanism: https://www.ncbi.nlm.nih.gov/books/NBK9989/ https://www.ncbi.nlm.nih.gov/books/NBK9989/ But left me wondering what the advantage of such mechanisms might be. Elsewhere in the same book they state: "One advantage is that it probably gives the species the benefits of sexual reproduction without tying the species to a 1:1 sex ratio. In crocodiles, in which temperature extremes produce females while moderate temperatures produce males, the sex ratio may be as great as 10 females to each male (Woodward and Murray 1993). The major disadvantage of temperature-dependent sex determination may be its narrowing of the temperature limits within which a species can exist. This means that thermal pollution (either locally or due to global warming) could conceivably eliminate a species in a given area (Janzen and Paukstis 1991). Ferguson and Joanen (1982) speculate that dinosaurs may have had temperature-dependent sex determination and that their sudden demise may have been caused by a slight change in temperature that created conditions wherein only males or only females hatched from their eggs."

MacsHeadroom 4y ago
In most cases one sex has more phenotypic variation, conferring greater survivability of the species in changing environments. In humans and most mammals it's males. But in nature sex is much more complex. I don't know a lot about reptiles. But perhaps this female swing will be ultimately good for them over time.
sigmaprimus 4y ago
I wonder if we are looking at it from the wrong point of view, yes the environment is warmer but that should be an advantage to reptiles. It would make sense that all the turtles would be more active in a warmer environment including their reproductive activities. Less but more active males plus more females equals more reproduction of the species. No?

by new299 4y ago

MacsHeadroom 4y ago

In most cases one sex has more phenotypic variation, conferring greater survivability of the species in changing environments. In humans and most mammals it's males. But in nature sex is much more complex. I don't know a lot about reptiles. But perhaps this female swing will be ultimately good for them over time.

sigmaprimus 4y ago

I wonder if we are looking at it from the wrong point of view, yes the environment is warmer but that should be an advantage to reptiles. It would make sense that all the turtles would be more active in a warmer environment including their reproductive activities. Less but more active males plus more females equals more reproduction of the species. No?