A phylogenetic analysis based on 18S small ribosomal subunit nuclear gene sequences suggested that Hawaiian spider mermithids are more closely related to a mainland presumptive Aranimemis species that infects spiders, than to an insect-infecting mermithid collected on Oahu, HI, or to Mermis nigrescens, also a parasite of insects.
The presence of two pairs of lungs on the same body segments as some extant forms provides a strong argument that they are most closely related to a group known as the tetrapulmonate arachnids, which includes the spiders, whip scorpions, whip spiders, and short-tailed whipscorpions (Dunlop 2010).
[other viewers concur] I feel like there's got to be some sort of psychological explanation for why that sticks out in all our minds, some deep-seated primal fear, maybe relating to spiders? "By the way, what was going on with the intro to movie?
However, while it is often assumed that findings relating to spiders are generalisable to other animals and may be extended to other objects and situations entirely, there is no reason why any findings regarding fear of spiders are immediately generalisable even to other animals, let alone to other types of fears.
So I started off last week doing a literature search on anything and everything related to hops and spider mites.
For example, arachnophobics are very attentive and responsive to spider-related stimuli — pictures of spiders, words or sentences related to spiders — but not to stimuli related to snakes; snake phobics have the opposite tendencies.
Although they seem to be related to land spiders, they also possess some unusual anatomy--including special compartments on their heads for carrying eggs--that suggest they may deserve their own branch of the arachnid family tree.
Pycnogonids are primarily marine arthropods, often considered closely related to chelicerates (spiders, scorpions and allies).
DNA evidence suggests velvet worms are closely related to crabs and spiders, possibly as a very early member of the group that gave rise to both.
As described in Biology Letters, the researchers studied two small fossils of trigonotarbids, an extinct order related to spiders, found in 300 million-year-old deposits at Coseley in England.
In addition, the horseshoe crab, a pre-dinosaur survivor more closely related to spiders than to crabs, contributes $50 million to the size of the drug and medical research industry.
