Sphex is a genus of cosmopolitan wasp that sting and paralyze prey insects. Sphex is one of many genera in the old digger wasp family Sphecidae (sensu lato), though most apart from the Sphecinae have now been moved to the family Crabronidae. There are over 130 known Sphex species.
Behavior In preparation for egg laying, they construct a protected "nest" (some species dig nests in the ground, while others use pre-existing holes) and then stock it with captured insects. Typically, the prey are left alive, but paralyzed by wasp toxins. The wasps lay their eggs in the provisioned nest and the wasp larvae feed on the paralyzed insects as they develop.
The great golden digger wasp (Sphex ichneumoneus) is found in North America. The developing wasps spend the winter in their nest. When the new generation of adults emerge, they contain the genetically programmed behaviors required to carry out another season of nest building. During the summer, a female might build as many as six nests, each with several compartments for her eggs. The building and provisioning of the nests takes place in a stereotypical, step-by-step fashion.
The Sphex Wasp Experiment Sphex has been shown, as in some Jean-Henri Fabre studies,Fabre, J.H. (1915/2001). The hunting wasps. New York: Dodd, Mead and Company. not to count how many crickets it collects for its nest. Although the wasp instinctively searches for four crickets, it cannot take into account a lost cricket, whether the cricket has been lost to ants or flies or simply been misplaced. Sphex drags its cricket prey towards its burrow by the antennae; if the antennae of the cricket are cut off, the wasp would not think to continue to pull its prey by a leg.
The navigation abilities of Sphex were studied by the ethologist Niko Tinbergen.Tinbergen, N. (1974). Curious naturalists (2nd Ed). Harmondsworth: Penguin. Richard Dawkins and Jane Brockmann later studied female rivalry over nesting holes in Sphex ichneumoneus.
Use in philosophy Some writers in the philosophy of mind, most notably Daniel Dennett, have cited the results of the Sphex Wasp Experiment for their arguments about human and animal free will.Dennett, Daniel (1973). "Mechanism and responsibility". In T. Honderich (Ed.), Essays on freedom of action. London: Routledge.
Some Sphex wasps drop a paralyzed insect near the opening of the nest. Before taking provisions into the nest, the Sphex first inspects the nest, leaving the prey outside. During the inspection, an experimenter can move the prey a few inches away from the opening. When the Sphex emerges from the nest ready to drag in the prey, it finds the prey missing. The Sphex quickly locates the moved prey, but now its behavioral "program" has been reset. After dragging the prey back to the opening of the nest, once again the Sphex is compelled to inspect the nest, so the prey is again dropped and left outside during another stereotypical inspection of the nest. This iteration can be repeated several times without the Sphex changing its sequence; by some accounts, endlessly. Dennett's argument quotes an account of Sphex behavior from Dean Wooldridge's Machinery of the Brain (1963).Dean Wooldridge (1963). The Machinery of the Brain. McGraw-Hill Douglas HofstadterHofstadter, Douglas (1985). "On the seeming paradox of mechanizing creativity". In Metamagical themas. Penguin. pp. 526–546. and Daniel Dennett have used this mechanistic behavior as an example of how seemingly thoughtful behavior can actually be quite mindless, the opposite of free will (or, as Hofstadter described it, sphexishness).
Philosopher Fred Keijzer challenges this use of Sphex, citing experiments in which behavioral adaptations are observed after many iterations. Keijzer sees the persistence of the Sphex example in cognitive theory as an indication of its rhetorical usefulness, not its factual accuracy. Keijzer also noted that repeated inspection of a disturbed nest may very well be an adaptive behavior, thus diminishing the aptness of Hofstadter's metaphor.
Species
The genus Sphex contains 132 extant species:
Sphex abyssinicus (Arnold, 1928) Sphex afer Lepeletier de Saint Fargeau, 1845 Sphex ahasverus Kohl, 1890 Sphex alacer Kohl, 1895 Sphex antennatus F. Smith, 1856 Sphex argentatissimus Dörfel and Ohl, 2015 Sphex argentatus Fabricius, 1787 Sphex argentinus Taschenberg, 1869 Sphex ashmeadi (Fernald, 1906) Sphex atropilosus Kohl, 1885 Sphex basilicus (R. Turner, 1915) Sphex bilobatus Kohl, 1895 Sphex bohemanni Dahlbom, 1845 Sphex brachystomus Kohl, 1890 Sphex brasilianus Saussure, 1867 Sphex brevipetiolatus Dörfel and Ohl, 2015 Sphex caelebs Dörfel and Ohl, 2015 Sphex caeruleanus Drury, 1773 Sphex caliginosus Erichson, 1849 Sphex camposi Campos, 1922 Sphex carbonicolor Van der Vecht, 1973 Sphex castaneipes Dahlbom, 1843 Sphex cognatus F. Smith, 1856 Sphex confrater Kohl, 1890 Sphex corporosus Dörfel and Ohl, 2015 Sphex cristi Genaro in Genaro & Juarrero, 2000 Sphex cubensis (Fernald, 1906) Sphex darwinensis R. Turner, 1912 Sphex decipiens Kohl, 1895 Sphex decoratus F. Smith, 1873 Sphex deplanatus Kohl, 1895 Sphex diabolicus F. Smith, 1858 Sphex dorsalis Lepeletier de Saint Fargeau, 1845 Sphex dorycus Guérin-Méneville, 1838 Sphex ephippium F. Smith, 1856 Sphex ermineus Kohl, 1890 Sphex erythrinus (Guiglia, 1939) Sphex ferrugineipes W. Fox, 1897 Sphex finschii Kohl, 1890 Sphex flammeus Dörfel and Ohl, 2015 Sphex flavipennis Fabricius, 1793 Sphex flavovestitus F. Smith, 1856 Sphex formosellus Van der Vecht, 1957 Sphex fortunatus Dörfel and Ohl, 2015 Sphex fumicatus Christ, 1791 Sphex fumipennis F. Smith, 1856 Sphex funerarius Gussakovskij, 1934 Sphex gaullei Berland, 1927 Sphex gilberti R. Turner, 1908 Sphex gracilis Dörfel and Ohl, 2015 Sphex gisteli Strand, 1916 Sphex guatemalensis Cameron, 1888 Sphex habenus Say, 1832 Sphex haemorrhoidalis Fabricius, 1781 Sphex ichneumoneus (Linnaeus, 1758) Sphex imporcatus Dörfel and Ohl, 2015 Sphex incomptus Gerstaecker, 1871 Sphex ingens F. Smith, 1856 Sphex inusitatus Yasumatsu, 1935 Sphex jamaicensis (Drury, 1773) Sphex jansei Cameron, 1910 Sphex jucundus Dörfel and Ohl, 2015 Sphex kolthoffi Gussakovskij, 1938 Sphex lanatus Mocsáry, 1883 Sphex latilobus Dörfel and Ohl, 2015 Sphex latreillei Lepeletier de Saint Fargeau, 1831 Sphex latro Erichson, 1849 Sphex leuconotus Brullé, 1833 Sphex libycus Beaumont, 1956 Sphex lucae Saussure, 1867 Sphex luctuosus F. Smith, 1856 Sphex madasummae Van der Vecht, 1973 Sphex malagassus Saussure, 1890 Sphex mandibularis Cresson, 1869 Sphex maroccanus Schmid-Egger, 2019 Sphex maximiliani Kohl, 1890 Sphex melanocnemis Kohl, 1885 Sphex melanopus Dahlbom, 1843 Sphex melas Gussakovskij, 1930 Sphex mendozanus Brèthes, 1909 Sphex mimulus R. Turner, 1910 Sphex mochii Giordani Soika, 1942 Sphex modestus F. Smith, 1856 Sphex muticus Kohl, 1885 Sphex neavei (Arnold, 1928) Sphex neoumbrosus Jha & Farooqui, 1996 Sphex nigrohirtus Kohl, 1895 Sphex nitidiventris Spinola, 1851 Sphex nudus Fernald, 1903 Sphex observabilis (R. Turner, 1918) Sphex opacus Dahlbom, 1845 Sphex optimus F. Smith, 1856 Sphex oxianus Gussakovskij, 1928 Sphex paulinierii Guérin-Méneville, 1843 Sphex pensylvanicus Linnaeus, 1763 Sphex permagnus (Willink, 1951) Sphex peruanus Kohl, 1890 Sphex praedator F. Smith, 1858 Sphex pretiosus Dörfel and Ohl, 2015 Sphex prosper Kohl, 1890 Sphex pruinosus Germar, 1817 Sphex resinipes (Fernald, 1906) Sphex resplendens Kohl, 1885 Sphex rex Hensen, 1991 Sphex rhodosoma (R. Turner, 1915) Sphex rufinervis Pérez, 1985 Sphex rufiscutis (R. Turner, 1918) Sphex rugifer Kohl, 1890 Sphex satanas Kohl, 1898 Sphex schlaeflei Schmid-Egger, 2019 Sphex schoutedeni Kohl, 1913 Sphex schrottkyi (Bertoni, 1918) Sphex semifossulatus Van der Vecht, 1973 Sphex sericeus (Fabricius, 1804) Sphex servillei Lepeletier de Saint Fargeau, 1845 Sphex solomon Hensen, 1991 Sphex stadelmanni Kohl, 1895 Sphex staudingeri Gribodo, 1894 Sphex subhyalinus W. Fox, 1899 Sphex subtruncatus Dahlbom, 1843 Sphex tanoi Tsuneki, 1974 Sphex taschenbergi Magretti, 1884 Sphex tepanecus Saussure, 1867 Sphex texanus Cresson, 1873 Sphex tinctipennis Cameron, 1888 Sphex tomentosus Fabricius, 1787 Sphex torridus F. Smith, 1873 Sphex vestitus F. Smith, 1856 Sphex walshae Hensen, 1991 Sphex wilsoni Hensen, 1991 Sphex zubaidiyacus Augul, 2013
Fossil Species
†Sphex bischoffi Zeuner, 1931 †Sphex giganteus Heer, 1867 †Sphex obscurus Statz, 1936
References
External links
Great golden digger wasp Sphex ichneumoneus - large format diagnostic photographs, wasp with katydid prey Online Identification Guide to eastern North American Sphex