How come this spiders egg ball is so perfect?

[Bruce Williams]

I've been watching a pair of P. phalangioides living in my downstairs cloakroom (pink walls) for quite some time now so was delighted to find her with a ball of eggs. Dad is still around watching from the opposite corner of the room.

Examining the photos on screen I was struck by just how perfectly spherical the ball of eggs was. My first thought was, "Wow - how did she gather all those eggs up into such a neat ball?" Then I realised that it would appear that she had laid exactly the right number of eggs to make a perfect sphere.

I wondered - if she'd laid one more or less eggs, would somehow the sphere still look perfect or would we see a solitary egg sitting on top of the sphere or maybe an egg sized gap in the sphere?





Bruce

[galanthus]

Bruce those are incredible shots

I have actually grown to love these spiders in my home, (I still hate all others due to extreme fear !! ), and they have even more respect from me now I've seen their amazing creation

[Action_Man]

This isent fair, you`ve got me searching the internet for images and counting counting all the eggs .

Cracking images as usual Bruce ...

[kharga]

Wow, what great pics!

[ron1863]

Either she can count or she just keeps laying eggs and sticks them together until she has the perfect ball shape. Wonder if she eats any extra that are laid though. Wonderful shots Bruce, hope your dad comes to like them

[Meta menardi]

It can't be said often enough, there are not answers to all the questions. If you can devise a way of answering this really quite fascinating question, you will add something to the sum of knowledge. What aboutcounting eggs, or measuring, or finding a female when she is producing the ball and removing some, and so on. Henri Fabre (search for electronic texts of his books, they are worth reading) was a master at devising ways to investigate this kind of thing.

[No.9 Spider]

Fantastic photo's as usual Bruce

I think each particular species lays an optimum amount. When I kept and bred the Theraphosidae (Tarantula) species over the years, I always found consistent egg counts for the species. Whereas some species regularly produced 200, another species regularly produced only 24 (usually larger spiderlings).
They know what they're doing anyway they've been at it for years, and the shape of each individual egg simply dictates the way they lie and the overall spherical shape they form.


No.9 Spider

[loripo]

The eggs look very regular in shape. Perhaps spheres clustered togther form larger spheres. They form hexagons on a flat surface tlike this:

(done for a Patterns in Nature Powerpoint) Dont know the maths regarding spheres though.

[Bruce Williams]

Thanks for all the great comments and the interesting info and suggestions everyone.

Ron - The "dad" I mentioned in my original post is the male spider. Well I'm pretty certain he's the proud father of those eggs as I've been watching the two of them interacting (sadly not actually mating) for some time.

Bruce

[pressld2]

fantastic shots as always Bruce!

I photographed a female with eggs last year but she didn't have as many as yours and they weren't in a perfect sphere...



Maybe she hadn't finished laying.

Dave P.