Research Update on Hymenopteran Nests and Cocoons, Upper Triassic Chinle Formation, Petrified Forest National Park, Arizona

STEPHEN T. HASIOTIS1, RUSSELL F. DUBIEL2, PAUL T. KAY3, TIMOTHY M. DEMKO4, KRYSTYNA KOWALSKA1 , and DOUGLAS MCDANIEL1

1Department of Geological Sciences, University of Colorado, Campus Box 399, Boulder, CO 80309-0399
2U.S. Geological Survey, Box 25046, Denver, CO 80225
3P.O. Box 18848, Denver, CO 80218
4Department of Earth Resources, Colorado State University, Fort Collins, CO 80523


Abstract—This paper updates our work-to-date on the bee and wasp (Hymenoptera: Aculeata) nest ichnofossils first discovered in Petrified Forest National Park (PEFO), Arizona, in 1993. Recent work includes the collection and the identification of new localities of bee nests and wasp cocoons (these are not elaborated on here to protect the sites). These hymenopteran ichnofossils were compared to other insect traces of nests and cocoons to demonstrate the differences in their architectures. The Triassic material was also compared to other bee and wasp nest and cocoons ichnofossils to illustrate their similar architecture. This is important because the ichnofossil evidence suggests that hymenopteran behavior has changed very little over 220 million years and that they were pollinators of plants in Triassic terrestrial ecosystems.

Introduction


Figure 1—Study area map with approximate positions of bee and wasp nests in Petrified Forest National Park, Arizona. Abbreviations: (PD) Painted Desert, (TE) Tepees.


Figure 2—Composite stratigraphic section of Triassic rocks within Petrified Forest National Park, Arizona. Arrows denote the stratigraphic positions of bee and wasp nest ichnofossils. Abbreviations: (b) bee nests, (w) wasp nests (cocoons).

After the initial discovery of Triassic bee and wasp(Hymenoptera: Aculeata) nest ichnofossils in Petrified Forest National Park (Hasiotis and Dubiel, 1993), additional specimens have been collected in the northern and southern portions of the Park (Figure 1, 2; Hasiotis et al., 1995, 1996; Hasiotis, 1997). The new specimens include the first known Triassic nests of bees in petrified wood and in paleosols from the Monitor Butte and Petrified Forest Members, and previously unknown casts of wasp cocoons in immature paleosols from the lowerpart of the Petrified Forest Member (Figure 1). In order to accurately define the ichnologic characters of fossil hymenopteran nests, the Triassic fossil material is compared to other bee and wasp ichnofossils from Mesozoic and Cenozoic continental deposits in North America (e.g., Brown, 1934; Retallack, 1984; Hasiotis and Demko, 1996; Bown et al., 1997; Hasiotis unpublished data). This overview updates on-going research on these new ichnofossils and emphasizes their significance to paleoecosystem analysis in continental deposits. The new ichnofossils serve as proxies for the presence of bees and wasps in the Triassic and preserved the interactions of these insects with the environment.

Hymenopteran Ichnofossil Evidence

Several types of ichnofossil hymenopteran (Aculeate) nests and cocoons occur as clusters of molds and casts in paleosols and silicified fossil logs in the Monitor Butte and Petrified Forest Members of the Upper Triassic Chinle Formation (Hasiotis et al., 1995, 1996; Hasiotis, 1997). All are nearly identical in size, shape, and micro-morphology to nests of extant primitively-social bees and gregarious wasps. These Triassic nests predate the earliest evidence of the aculeates from body fossils by more than 100 million years. Here we report new evidence of hymenopteran ichnofossils from new localities with members mentioned above in the Painted Desert and in Rainbow Forest of PEFO.

Bee nests.—Flask-shaped, smooth-walled cells approximately 20 mm long occur as circular and linear clusters that form multi-tiers of cells. Nests in paleosols exhibit at least three distinct configurations: (1) linear strings of up to ten cells; (2) radial clusters of up to 100 cells in groups of three or four; and (3) tightly constructed clusters of up to twelve cells with shared walls (Figure 3A, 4A). Nests within silicified logs were constructed in areas below the bark in the heartwood, including areas with knots formed by fallen tree limbs (Figure 5A-B, 4B). Some of these cells have caps that are sometimes woven and spiral, like those of extant bee nests, and contain black, spherical balls or pellets about 4 mm in diameter that appear to contain plant matter, pollen, and other unidentifiable material. The complex, highly organized clusters of cells suggests cooperation between numerous constructors working together to make a large nest with a repetitive bauplan. The comparison of Triassic nest architecture and contents to extant bee nests suggest that Triassic hymenopterans probably foraged for gymnosperm and cycadeiod pollen, resins, ascomycete and rust spores, and other plant fluids for nutrients and cell provisioning. Modern hymenopteran (Halictidae and Anthophoridae) nests of similar construction often reflect some degree of social interaction between the egg producer (queen) and the workers, in which the offspring of the founding female become workers and assist with nest construction and provisioning (Michener, 1974). Triassic hymenopterans may also have scavenged carrion (flesh and fluid), as do some modern species of halictid, anthophorid, trigoniid, and meliponine bees (Michener, 1974).

Since modern bees line the cells of their nests with organic compounds produced from their Dufour's gland, we analyzed the ichnofossil nest cells for chemical evidence that bees constructed the nests. Organic chemical analysis of the wall linings of the cells in the bee nests (Kay et al., 1997) yielded biochemical evidence of a phylogenetic link to modern bees in the Anthophoridae and Colletidae. Gas chromatography-mass spectrometry/mass spectrometry techniques released straight-chain carbon molecules from the bee nest cell walls. This organic material today is only found in socially varied bees and is produced from the Dufour's gland (Michener, 1974). The chemical analysis also demonstrates that despite the silicification of the wood, organic carbon is preserved in forms that can be identified to particular organisms.

Wasp nests.— Spindle-shaped casts and molds interpreted to be cocoons about 10-35 mm long are also found in paleosols (Figure 3B). These occur in clusters of four to ten individuals, each showing a woven, thread-like surficial morphology. The cocoon morphology, nest configuration, and nesting site distribution strongly resemble constructions of modern gregarious sphecid wasps (Evans, 1963), which nest in close proximity to one another, construct nests with of four to twenty cells, and whose larvae spin cocoons with a sturdy silken weave. The cells of these Triassic nests were probably provisioned with insects and other carrion materials in a fashion similar to modern wasp provisioning (Hasiotis, 1997).

Comparison With Other Reproductive Insect Behavior

When reproductive structures of xyelid wasps (Symphyta, sawflies), various beetles (Coleoptera), and moths (Lepidoptera) (Essig, 1926; Keen, 1939) are compared to the Triassic nest and cocoon ichnofossils, all of these insects are ruled out as the constructors of the Triassic structures based on the morphology of their nests and borings. Although modern xyelid and other symphytid wasp larvae bore into coniferous wood, they construct relatively simple borings, with primitive hollowed-out structures for pupation, and are relatively dispersed rather than tightly clustered in the heartwood. Like their Mesozoic representatives, modern Cupedoidea beetles (e.g., Scolytidae, Cupedidae, and Platypodidae) construct reproductive structures that contain radially-arranged galleries from central tunnels that are poorly-organized in plan and loosely-connected as a series of short galleries extending from central galleries. These radiating galleries are subsequently expanded by the growing larvae and become wider as they are excavated away from the central tunnel (Essig, 1926). Cocoons of modern moths and butterflies are commonly either very large (>30 mm), or slender (4:1 length to width), or have the form and size of the pupa (Essig, 1926). They do not exhibit a delicate weave pattern, but rather show delicate masses of silken strands. However grossly similar, these and other reproductive puparia of sawflies, beetles, and moths are not as complex, organized, or crafted as are the Triassic ichnofossils that are clearly more structurally similar to the constructions of bees and wasps.

Figure 3A, Plan view of a portion of a bee nest in an immature paleosol, Monitor Butte Member, Tepees. B, Wasp cocoon molds (and casts-removed in photo) in an immature paleosol, Monitor Butte Member, Tepees.

Figure 4—Triassic life-reconstructions of bee nests (A) a soil and (B) a conifer, Araucarioxylon arizonicum.

New Comparative Evidence Of Hymenopteran Ichnofossil Nests

The morphology of Triassic bee and wasp ichnofossils compare favorably with hynemopteran ichnofossils collected from the Upper Jurassic Morrison Formation (Utah), the Lower Cretaceous Dakota Formation, the Upper Cretaceous Two Medicine Formation (Montana), the Paleocene-Eocene Claron Formation (Utah), the Eocene Brian Head Formation (Utah), the Eocene Bridger Formation (Wyoming), the Miocene of Greece (Santorini), and the Holocene dunes in Great Sand Dunes National Monument (Colorado) (Hasiotis et al., in preparation). Nearly 200 bee cells and over 1000 wasp cocoons have been collected from these units. Preliminary measurements of the cells collected from nests in paleosols share strikingly similar proportions between the cell length and the widest and narrowest segments of the cell with those proportions found in Triassic bee cells in xylic substrates and paleosols. Preliminary measurements of well-preserved cocoons collected from paleosols also share corresponding proportions between cocoon length and width with those proportions found in Triassic cocoons. All the Mesozoic and Cenozoic cells and cocoons preserve at least three size ranges of both wasp cocoons and bee cells. Two other size ranges are also being discriminated quantitatively from the deposits mentioned above and probably represent puparia of moths (Lepidoptera) and beetles (Coleoptera). These moth and beetle insect traces are clearly different from the hymenopteran cocoons: moth cocoons are typically barrel-shaped, and occur in paleosols rather than in xylic substrates; beetle traces are spherical to hemispherical in morphology and also occur in paleosols. The additional information from the beetle and moth cocoons further strengths our argument that we can discriminate between hymenopteran and non-hymenopteran ichnofossils.

Significance

Late Triassic ichnofossil insect nests record very early, yet advanced behavioral and morphological characteristics of the Hymenoptera. These trace fossils shed new light on hypotheses regarding the timing of insect diversification and its co-evolution with plants in terrestrial ecosystems. Insect ichnofossils better constrain the age of origination of numerous groups because they have a greater preservation potential than do body fossils, which are typically much rarer. Triassic ichnofossils of derived hymenopteran insects extend the ages of these insects by more than 100 million years (Hasiotis et al., 1995, 1996). Hymenopteran ichnofossils reveal more information about behavior than do body fossils, which can be used to interpret behavior solely through functional morphology. The highly organized nest configurations of Triassic hymenopteran ichnofossils imply that complex behavior reflecting primitive socialization and pollenization, was established long before the advent of angiosperms; these organisms were acting as pollinators in the Triassic terrestrial ecosystems. The pre-established plant foraging and feeding strategies of early Mesozoic hymenopterans constitute a pre-adaptation for a later origin of pollination mechanisms in early angiosperms, thus favoring rapid angiosperm radiation and diversification. Through time, these and other insects probably switched plant resources (from gymnosperm-cycadeiod to angiosperm) as they co-evolved with the rapidly diversifying angiosperms to form the intricate ecological relationships exhibited by insects and angiosperms today.

Figure 5A, Plan view of a circular portion of a bee nest in a petrified log, Black Forest bed, Petrified Forest Member, Painted Desert. B, Plan view of a linear portion of a bee nest in a petrified log (continuation of nest above), Black Forest bed, Petrified Forest Member, Painted Desert.

Acknowledgments

We thank the park superintendents, rangers, resource managers, paleontologists, administrative and field personal, interns, and colleagues who have assisted our research over the years at Petrified Forest National Park, Arizona. Without their support and foresight, this work would not be possible. We also thank Adolf Coors and the Colorado School of mines for use of their SEM and Gas Chromatograph. This work is part of a dissertation conducted by STH at the University of Colorado, Boulder and is also paleontology research projects by KK and DM at the Museum at the University of Colorado, Boulder.

References

Brown, R. W. 1934. Celliforma spirifer, the fossil larval chambers of mining bees. Washington Academy of Science Journal, 24:532-539.

hasiotis et al.—pefo, triassic bee nest

Bown, T. M., S. T. Hasiotis, J. F. Genise, F. Maldonado, and E. M. Brouwers. 1997. Trace fossils of ants (Formicidae) and other hymenopterous insects, Claron Formation (Eocene), southwestern Utah. U.S. Geological Survey Bulletin 2153, p. 41-58.

Essig, E. O. 1926. Insects of Western North America. MacMillan Company, NewYork, 1035 p.

Evans, H. E. 1963. Wasp Farm. Cornell University Press, Ithaca, 178 p.

Hasiotis, S. T. 1997. Abuzz before flowers... Plateau Journal, Museum of Northern Arizona, 1:20-27.

———, T. M. Bown, P. T. Kay, R. F. Dubiel, and T. M. Demko. 1996. The ichnofossil record of hymenopteran nesting behavior from Mesozoic and Cenozoic pedogenic and xylic substrates: Example of relative stasis. North American Paleontological Convention, NAPC-96, Washington, DC, p. 165.

———, and T. M. Demko. 1996. Terrestrial and freshwater trace fossils, Upper Jurassic Morrison Formation, Colorado Plateau. Continental Jurassic Symposium, Museum of Northern Arizona, Number 60, p. 355-370.<

Research Update on Hymenopteran Nests and Cocoons, Upper Triassic Chinle Formation, Petrified Forest National Park, Arizona

STEPHEN T. HASIOTIS1, RUSSELL F. DUBIEL2, PAUL T. KAY3, TIMOTHY M. DEMKO4, KRYSTYNA KOWALSKA1 , and DOUGLAS MCDANIEL1

1Department of Geological Sciences, University of Colorado, Campus Box 399, Boulder, CO 80309-0399
2U.S. Geological Survey, Box 25046, Denver, CO 80225
3P.O. Box 18848, Denver, CO 80218
4Department of Earth Resources, Colorado State University, Fort Collins, CO 80523


Abstract—This paper updates our work-to-date on the bee and wasp (Hymenoptera: Aculeata) nest ichnofossils first discovered in Petrified Forest National Park (PEFO), Arizona, in 1993. Recent work includes the collection and the identification of new localities of bee nests and wasp cocoons (these are not elaborated on here to protect the sites). These hymenopteran ichnofossils were compared to other insect traces of nests and cocoons to demonstrate the differences in their architectures. The Triassic material was also compared to other bee and wasp nest and cocoons ichnofossils to illustrate their similar architecture. This is important because the ichnofossil evidence suggests that hymenopteran behavior has changed very little over 220 million years and that they were pollinators of plants in Triassic terrestrial ecosystems.

Introduction


Figure 1—Study area map with approximate positions of bee and wasp nests in Petrified Forest National Park, Arizona. Abbreviations: (PD) Painted Desert, (TE) Tepees.


Figure 2—Composite stratigraphic section of Triassic rocks within Petrified Forest National Park, Arizona. Arrows denote the stratigraphic positions of bee and wasp nest ichnofossils. Abbreviations: (b) bee nests, (w) wasp nests (cocoons).

After the initial discovery of Triassic bee and wasp(Hymenoptera: Aculeata) nest ichnofossils in Petrified Forest National Park (Hasiotis and Dubiel, 1993), additional specimens have been collected in the northern and southern portions of the Park (Figure 1, 2; Hasiotis et al., 1995, 1996; Hasiotis, 1997). The new specimens include the first known Triassic nests of bees in petrified wood and in paleosols from the Monitor Butte and Petrified Forest Members, and previously unknown casts of wasp cocoons in immature paleosols from the lowerpart of the Petrified Forest Member (Figure 1). In order to accurately define the ichnologic characters of fossil hymenopteran nests, the Triassic fossil material is compared to other bee and wasp ichnofossils from Mesozoic and Cenozoic continental deposits in North America (e.g., Brown, 1934; Retallack, 1984; Hasiotis and Demko, 1996; Bown et al., 1997; Hasiotis unpublished data). This overview updates on-going research on these new ichnofossils and emphasizes their significance to paleoecosystem analysis in continental deposits. The new ichnofossils serve as proxies for the presence of bees and wasps in the Triassic and preserved the interactions of these insects with the environment.

Hymenopteran Ichnofossil Evidence

Several types of ichnofossil hymenopteran (Aculeate) nests and cocoons occur as clusters of molds and casts in paleosols and silicified fossil logs in the Monitor Butte and Petrified Forest Members of the Upper Triassic Chinle Formation (Hasiotis et al., 1995, 1996; Hasiotis, 1997). All are nearly identical in size, shape, and micro-morphology to nests of extant primitively-social bees and gregarious wasps. These Triassic nests predate the earliest evidence of the aculeates from body fossils by more than 100 million years. Here we report new evidence of hymenopteran ichnofossils from new localities with members mentioned above in the Painted Desert and in Rainbow Forest of PEFO.

Bee nests.—Flask-shaped, smooth-walled cells approximately 20 mm long occur as circular and linear clusters that form multi-tiers of cells. Nests in paleosols exhibit at least three distinct configurations: (1) linear strings of up to ten cells; (2) radial clusters of up to 100 cells in groups of three or four; and (3) tightly constructed clusters of up to twelve cells with shared walls (Figure 3A, 4A). Nests within silicified logs were constructed in areas below the bark in the heartwood, including areas with knots formed by fallen tree limbs (Figure 5A-B, 4B). Some of these cells have caps that are sometimes woven and spiral, like those of extant bee nests, and contain black, spherical balls or pellets about 4 mm in diameter that appear to contain plant matter, pollen, and other unidentifiable material. The complex, highly organized clusters of cells suggests cooperation between numerous constructors working together to make a large nest with a repetitive bauplan. The comparison of Triassic nest architecture and contents to extant bee nests suggest that Triassic hymenopterans probably foraged for gymnosperm and cycadeiod pollen, resins, ascomycete and rust spores, and other plant fluids for nutrients and cell provisioning. Modern hymenopteran (Halictidae and Anthophoridae) nests of similar construction often reflect some degree of social interaction between the egg producer (queen) and the workers, in which the offspring of the founding female become workers and assist with nest construction and provisioning (Michener, 1974). Triassic hymenopterans may also have scavenged carrion (flesh and fluid), as do some modern species of halictid, anthophorid, trigoniid, and meliponine bees (Michener, 1974).

Since modern bees line the cells of their nests with organic compounds produced from their Dufour's gland, we analyzed the ichnofossil nest cells for chemical evidence that bees constructed the nests. Organic chemical analysis of the wall linings of the cells in the bee nests (Kay et al., 1997) yielded biochemical evidence of a phylogenetic link to modern bees in the Anthophoridae and Colletidae. Gas chromatography-mass spectrometry/mass spectrometry techniques released straight-chain carbon molecules from the bee nest cell walls. This organic material today is only found in socially varied bees and is produced from the Dufour's gland (Michener, 1974). The chemical analysis also demonstrates that despite the silicification of the wood, organic carbon is preserved in forms that can be identified to particular organisms.

Wasp nests.— Spindle-shaped casts and molds interpreted to be cocoons about 10-35 mm long are also found in paleosols (Figure 3B). These occur in clusters of four to ten individuals, each showing a woven, thread-like surficial morphology. The cocoon morphology, nest configuration, and nesting site distribution strongly resemble constructions of modern gregarious sphecid wasps (Evans, 1963), which nest in close proximity to one another, construct nests with of four to twenty cells, and whose larvae spin cocoons with a sturdy silken weave. The cells of these Triassic nests were probably provisioned with insects and other carrion materials in a fashion similar to modern wasp provisioning (Hasiotis, 1997).

Comparison With Other Reproductive Insect Behavior

When reproductive structures of xyelid wasps (Symphyta, sawflies), various beetles (Coleoptera), and moths (Lepidoptera) (Essig, 1926; Keen, 1939) are compared to the Triassic nest and cocoon ichnofossils, all of these insects are ruled out as the constructors of the Triassic structures based on the morphology of their nests and borings. Although modern xyelid and other symphytid wasp larvae bore into coniferous wood, they construct relatively simple borings, with primitive hollowed-out structures for pupation, and are relatively dispersed rather than tightly clustered in the heartwood. Like their Mesozoic representatives, modern Cupedoidea beetles (e.g., Scolytidae, Cupedidae, and Platypodidae) construct reproductive structures that contain radially-arranged galleries from central tunnels that are poorly-organized in plan and loosely-connected as a series of short galleries extending from central galleries. These radiating galleries are subsequently expanded by the growing larvae and become wider as they are excavated away from the central tunnel (Essig, 1926). Cocoons of modern moths and butterflies are commonly either very large (>30 mm), or slender (4:1 length to width), or have the form and size of the pupa (Essig, 1926). They do not exhibit a delicate weave pattern, but rather show delicate masses of silken strands. However grossly similar, these and other reproductive puparia of sawflies, beetles, and moths are not as complex, organized, or crafted as are the Triassic ichnofossils that are clearly more structurally similar to the constructions of bees and wasps.

Figure 3A, Plan view of a portion of a bee nest in an immature paleosol, Monitor Butte Member, Tepees. B, Wasp cocoon molds (and casts-removed in photo) in an immature paleosol, Monitor Butte Member, Tepees.

Figure 4—Triassic life-reconstructions of bee nests (A) a soil and (B) a conifer, Araucarioxylon arizonicum.

New Comparative Evidence Of Hymenopteran Ichnofossil Nests

The morphology of Triassic bee and wasp ichnofossils compare favorably with hynemopteran ichnofossils collected from the Upper Jurassic Morrison Formation (Utah), the Lower Cretaceous Dakota Formation, the Upper Cretaceous Two Medicine Formation (Montana), the Paleocene-Eocene Claron Formation (Utah), the Eocene Brian Head Formation (Utah), the Eocene Bridger Formation (Wyoming), the Miocene of Greece (Santorini), and the Holocene dunes in Great Sand Dunes National Monument (Colorado) (Hasiotis et al., in preparation). Nearly 200 bee cells and over 1000 wasp cocoons have been collected from these units. Preliminary measurements of the cells collected from nests in paleosols share strikingly similar proportions between the cell length and the widest and narrowest segments of the cell with those proportions found in Triassic bee cells in xylic substrates and paleosols. Preliminary measurements of well-preserved cocoons collected from paleosols also share corresponding proportions between cocoon length and width with those proportions found in Triassic cocoons. All the Mesozoic and Cenozoic cells and cocoons preserve at least three size ranges of both wasp cocoons and bee cells. Two other size ranges are also being discriminated quantitatively from the deposits mentioned above and probably represent puparia of moths (Lepidoptera) and beetles (Coleoptera). These moth and beetle insect traces are clearly different from the hymenopteran cocoons: moth cocoons are typically barrel-shaped, and occur in paleosols rather than in xylic substrates; beetle traces are spherical to hemispherical in morphology and also occur in paleosols. The additional information from the beetle and moth cocoons further strengths our argument that we can discriminate between hymenopteran and non-hymenopteran ichnofossils.

Significance

Late Triassic ichnofossil insect nests record very early, yet advanced behavioral and morphological characteristics of the Hymenoptera. These trace fossils shed new light on hypotheses regarding the timing of insect diversification and its co-evolution with plants in terrestrial ecosystems. Insect ichnofossils better constrain the age of origination of numerous groups because they have a greater preservation potential than do body fossils, which are typically much rarer. Triassic ichnofossils of derived hymenopteran insects extend the ages of these insects by more than 100 million years (Hasiotis et al., 1995, 1996). Hymenopteran ichnofossils reveal more information about behavior than do body fossils, which can be used to interpret behavior solely through functional morphology. The highly organized nest configurations of Triassic hymenopteran ichnofossils imply that complex behavior reflecting primitive socialization and pollenization, was established long before the advent of angiosperms; these organisms were acting as pollinators in the Triassic terrestrial ecosystems. The pre-established plant foraging and feeding strategies of early Mesozoic hymenopterans constitute a pre-adaptation for a later origin of pollination mechanisms in early angiosperms, thus favoring rapid angiosperm radiation and diversification. Through time, these and other insects probably switched plant resources (from gymnosperm-cycadeiod to angiosperm) as they co-evolved with the rapidly diversifying angiosperms to form the intricate ecological relationships exhibited by insects and angiosperms today.

Figure 5A, Plan view of a circular portion of a bee nest in a petrified log, Black Forest bed, Petrified Forest Member, Painted Desert. B, Plan view of a linear portion of a bee nest in a petrified log (continuation of nest above), Black Forest bed, Petrified Forest Member, Painted Desert.

Acknowledgments

We thank the park superintendents, rangers, resource managers, paleontologists, administrative and field personal, interns, and colleagues who have assisted our research over the years at Petrified Forest National Park, Arizona. Without their support and foresight, this work would not be possible. We also thank Adolf Coors and the Colorado School of mines for use of their SEM and Gas Chromatograph. This work is part of a dissertation conducted by STH at the University of Colorado, Boulder and is also paleontology research projects by KK and DM at the Museum at the University of Colorado, Boulder.

References

Brown, R. W. 1934. Celliforma spirifer, the fossil larval chambers of mining bees. Washington Academy of Science Journal, 24:532-539.

hasiotis et al.—pefo, triassic bee nest

Bown, T. M., S. T. Hasiotis, J. F. Genise, F. Maldonado, and E. M. Brouwers. 1997. Trace fossils of ants (Formicidae) and other hymenopterous insects, Claron Formation (Eocene), southwestern Utah. U.S. Geological Survey Bulletin 2153, p. 41-58.

Essig, E. O. 1926. Insects of Western North America. MacMillan Company, NewYork, 1035 p.

Evans, H. E. 1963. Wasp Farm. Cornell University Press, Ithaca, 178 p.

Hasiotis, S. T. 1997. Abuzz before flowers... Plateau Journal, Museum of Northern Arizona, 1:20-27.

———, T. M. Bown, P. T. Kay, R. F. Dubiel, and T. M. Demko. 1996. The ichnofossil record of hymenopteran nesting behavior from Mesozoic and Cenozoic pedogenic and xylic substrates: Example of relative stasis. North American Paleontological Convention, NAPC-96, Washington, DC, p. 165.

———, and T. M. Demko. 1996. Terrestrial and freshwater trace fossils, Upper Jurassic Morrison Formation, Colorado Plateau. Continental Jurassic Symposium, Museum of Northern Arizona, Number 60, p. 355-370.

———, and R. F. Dubiel. 1993. Trace fossil assemblages in Chinle
Formation alluvial deposits at the Tepees, Petrified Forest National Park, Arizona. In Lucas, S. G. and Morales, M. The Nonmarine Triassic - Field Guidebook, New Mexico Museum of Natural History Bulletin, 3:G42-G43.

———, ———, and T. Demko. 1995. Triassic hymenopterous nests: Insect eusociality predates Angiosperm plants: Rocky Mountain Section, Geological Society of America Regional Meeting, 27(4):13.

Kay, P. T., D. King, and S. T. Hasiotis. 1997. Petrified Forest National Park Upper Triassic trace fossils yield biochemical evidence of phylogenetic link to modern bees (Hymenoptera: Apoidea). Geological Society of America National Meeting, Salt Lake City, UT, 29(6):102.

Keen, F. P. 1939. Insect Enemies of Western Forests. U.S. Department of Agriculture Misc. Publication No. 273, 209 p.

Michener, C. D. 1974. The social behavior of the bees. Harvard University Press, Cambridge, Massachusetts, 404 p.

Retallack, G. J. 1984. Trace fossils of burrowing beetles and bees in an Oligocene paleosol, Badlands National Park, South Dakota. Journal of Paleontology, 58:571-592.

Go to Nature Net Home Page . Go to Park Net Home Page
P>———, and R. F. Dubiel. 1993. Trace fossil assemblages in Chinle
Formation alluvial deposits at the Tepees, Petrified Forest National Park, Arizona. In Lucas, S. G. and Morales, M. The Nonmarine Triassic - Field Guidebook, New Mexico Museum of Natural History Bulletin, 3:G42-G43.

———, ———, and T. Demko. 1995. Triassic hymenopterous nests: Insect eusociality predates Angiosperm plants: Rocky Mountain Section, Geological Society of America Regional Meeting, 27(4):13.

Kay, P. T., D. King, and S. T. Hasiotis. 1997. Petrified Forest National Park Upper Triassic trace fossils yield biochemical evidence of phylogenetic link to modern bees (Hymenoptera: Apoidea). Geological Society of America National Meeting, Salt Lake City, UT, 29(6):102.

Keen, F. P. 1939. Insect Enemies of Western Forests. U.S. Department of Agriculture Misc. Publication No. 273, 209 p.

Michener, C. D. 1974. The social behavior of the bees. Harvard University Press, Cambridge, Massachusetts, 404 p.

Retallack, G. J. 1984. Trace fossils of burrowing beetles and bees in an Oligocene paleosol, Badlands National Park, South Dakota. Journal of Paleontology, 58:571-592.