Childress, J. J., H. Felbeck, and G. N. Somero.
1987. Symbiosis in the deep sea. Sci. Am. 256:114–120 (May). The amazing story of
how the animals around deep-sea vents,
including Riftia pachyptila, manage to
absorb hydrogen sulfide and transport it to
their mutualistic bacteria. For most animals,
hydrogen sulfide is highly toxic.
Crowe, J. H., and A. F. Cooper, Jr. 1971. Cryptobiosis.
Sci. Am. 225:30–36 (Dec.). Cryptobiotic
nematodes, rotifers, and tardigrades
can withstand adverse conditions of astonishing
rigor, yet perceptible metabolism
continues in their state of suspended
Gould, S. J. 1995. Of tongue worms, velvet
worms, and water bears. Natural History 104(1):6–15. Intriguing essay on affinities
of Pentastomida, Onychophora, and
Tardigrada and how they, along with larger
phyla, were products of the Cambrian
Haugerud, R. E. 1989. Evolution in the pentastomids.
Parasitol. Today 5:126–132. Much
remains to be learned of this puzzling
group, but there is strong evidence of its
Hoffman, P. F., and D. P. Schrag. 2000. Snowball
Earth. Sci. Am. 282:68–75 (Jan.). It appears
that an extreme ice age prevailed on earth
600 million years ago, followed by an extremely warm period fueled by a brutal
greenhouse effect. Did these events precipitate
the Cambrian explosion?
Rice, M. E., and M. Todorovic (eds). 1975. Proceedings
of the International Symposium
on the biology of the Sipuncula and
Echiura, 2 vols. Washington, D.C., National
Museum of Natural History. A series of
technical articles, but much of interest for
further reading on these two phyla.
Southward, E. C. 1975. Fine structure and phylogeny
of the Pogonophora. In E. J. W.
Barrington and R. P. S. Jefferies, (eds). Protochordates.
London, Zoological Society of
London, no. 36.