Pharyngula

Fossil spiders!

Comments

  1. #1 garth
    July 29, 2006

    i have mygalomorphs living in my room right now. those big, powerful spiders are a thing of beauty.
    H. lividum is a particularly beautiful creature amongst many.

  2. #2 garth
    July 29, 2006

    also, check out the solfugids, the infamous “camel spiders”. tip: they do not get bigger than 6″. they are not poisonous. they cannot jump.
    they are amazing animals though.

  3. #3 Daryl McCullough
    July 29, 2006

    I recently heard a hypothesis (I have no idea whether there is any basis for it or not) that spiders (or some 8-legged ancestor of spiders) evolved before 6-legged insects. The wings of insects are (according to this hypothesis) a mutation of two of the legs of the pre-spider, leaving 6 legs.

    Does anybody know whether this is generally accepted or not?

  4. #4 JohnnieCanuck
    July 29, 2006

    The part I liked was, “thus this occurrence extends the family record by some 90 myr”. What a thrill for Selden et al.

    My education here is continuing apace. ‘Lagerst├Ątten’ is now part of my reading vocabulary.

    Thank you PZ.

  5. #5 j
    July 29, 2006

    Ewww.

    I don’t like spiders.

  6. #6 Space Parasite
    July 29, 2006

    Daryl — insect wings are probably repurposed gills. Check down a few entries in this very blog for some more information.

  7. #7 Loren Petrich
    July 30, 2006

    That’s certainly an interesting idea, insects evolving from arachnids, but there’s good reason to think otherwise, that insects are instead most closely related to crustaceans.

    Insect segments:

    1: H1: Eyes
    2: H2: Antennae
    3: H3: none (crustaceans: second pair of antennae)
    4: H4: Mandibles (mouthparts)
    5: H5: Maxillae (mouthparts)
    6: H6: Labium (mouthpart)
    7: T1: Legs, wings in very early insects
    8: T2: Legs, wings
    9: T3: Legs, wings
    10: A1: none (crustaceans may have additional pairs of legs)

    Arachnid segments:

    1: H1: Eyes
    2: H2: Chelicerae (fangs)
    3: H3: Pedipalps (“arms”)
    4: H4: Legs
    5: H5: Legs
    6: H6: Legs
    7: H7: Legs
    8: A1: none

    H = head / prosoma
    T = thorax
    A = abdomen / opisthosoma

    So spiders walk with limbs that insects eat with.

  8. #8 Bob Dowling
    July 31, 2006

    That’s not a fossil spider!
    This is a fossil spider!

    (I can’t find photos of the fossil cast itself. I’ll have to hunt down some postcards at the museum.)

  9. #9 garth
    July 31, 2006

    probably too late for anyone to read this, but hereis Megarachne, the monster fossil spider.
    Isn’t there a limit on the size land-based invertebrates can reach? what about land-based invertebrates that molt in the sea? that could make for some big bastards.

  10. #10 tahlia
    December 3, 2007

    i love spiders

  11. #11 kirsty
    December 12, 2007

    oh i say

  12. #12 kirsty
    December 12, 2007

    lookin at these spiders makes me even scared than what i was so why show them. the people out thare that has a phoia of them and you still show them WOW there spiders you dont see them puting pictures of you all over the computer so why do it. i just dont no why people think that they have the right to do something like that at the end of the day some might bite because people are winding them up takeing pictures i dont see many people takin pictures of ants etc……. WHY DO IT .ITS WRONG IN MY EYES…………

  13. #13 james
    December 12, 2007

    i don’t like spiders but i do like turtles so i am happy with a turtle any day

  14. #14 shannon mclimore
    February 22, 2008

    thats just the way roll!!

  15. #15 shannon mclimore
    February 22, 2008

    thats just the way roll!!

  16. #16 shannon mclimore
    February 22, 2008

    thats just the way roll!!

  17. #17 shannon mclimore
    February 22, 2008

    thats just the way roll!!

  18. #18 Stacie
    March 20, 2008

    I hate spiders! Ewwwwwwwwwwwwwwwwww! They are so gross how could you like them?

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