butterfly prenatal development

[Chris J. Durden]

Early larval development may be very different in closely related 
butterflies. The Arctic *Colias hecla* lays eggs on legumes that later 
hatch into first instar larvae. High arctic populations that are currently 
considered to belong to the same species are ovoviviparous. They lay first 
instar larvae on willows in Ellesmere, Northern Greenland and Lapland.
................Chris Durden

At 11:17 AM 8/7/2003 -0400, you wrote:
>Jim at gpnc.org writes:
> >Or is there some
> >unformed pre-larva in butterfly eggs that has to finish developing before
> >it
> >hatches?
>
> >>>>Let's get technical here (pardon to biologists).  An egg is the gamete
>that the female produces, before the sperm fertilizes it.  Upon
>fertilization, the "egg" is now a zygote (still single-celled).  Sooner or
>later, it undergoes repeated cell divisions, followed by cell movements.
>At this early stage of development the new organism can be called an
>embryo, but its cellular arrangements don't closely resemble a larva.  One
>could indeed call it a "pre-larva."  Gradually, the cells interact, become
>differented into functional cells of many types, and continue movements
>until the form of a larva becomes apparent.  It is still within the shell
>of the original egg, and looks outwardly like the original egg.  But it is
>at this point a pre-emergent larva.
>
>Here's where my expertise wanes.  I suspect, but don't know, that among
>those tens of thousands of lep species, there are all varieties as to how
>far along the embryo has come toward being a larva when the female
>deposits it.  Using the fruit fly as a possible model, it is entirely
>conceivable (pardon the pun) that all or  much of the embryonic cell
>movements and changes can occur after deposition--fruit fly "eggs" go
>through all of the pre-larval changes after the mom lays them, and all
>within just a few days until the larva hatches.
>
>
>John Snyder
>Dept. of Biology
>Furman University
>Greenville, SC USA
>
>
>
>
>  ------------------------------------------------------------
>
>    For subscription and related information about LEPS-L visit:
>
>    http://www.peabody.yale.edu/other/lepsl
>



 
 ------------------------------------------------------------ 

   For subscription and related information about LEPS-L visit:

   http://www.peabody.yale.edu/other/lepsl