Reef organisms are well known for engaging in photosymbiosis in which a heterotrophic protist or ... more Reef organisms are well known for engaging in photosymbiosis in which a heterotrophic protist or animal host partners with one or more kinds of photosynthetic microbes. This relationship provides metabolic advantages in nutrition and rapid calcification, often leading to secretion of massive skeletons in the host. In turn the symbiont receives protection, physical stability in the photic zone and direct access to the sun's energy. On an evolutionary scale, this relationship provided strong selective pressures for producing the algal-host relationship and has occurred multiple times in geological history. Today, different kinds of algae (dinoflagellates, diatoms, chlorophytes, rhodophytes, and cyanobacteria) inhabit various hosts (foraminifera, corals, mollusks) in modern reefs, and multiple phylogenetically separate algae may have also inhabited phylogenetically distinct ancient animals and protists. The modern dinoflagellate photosymbiont Symbiodinium occurs in a wide variety of unrelated host organisms from protists to mollusks. Molecular data indicate this genus first evolved either after the end-Cretaceous mass extinction 65 my ago or in the Early Eocene some 55 my ago. Encysted dinoflagellates related to Symbiodinium have been traced to the Triassic, and photosymbiosis may have been involved in even earlier reef associations. In all fossils, however, the identity of ancient photosymbionts is difficult to establish because they rarely, if ever, fossilize. Nevertheless, indirect evidence indicates that photosymbiotic ecosystems existed at least as far back as the Cambrian. Inferential lines of evidence, including large colony size, massive skeletons,
Although reef-like structures formed in the Neoproterozoic, reefs built by metazoans did not appe... more Although reef-like structures formed in the Neoproterozoic, reefs built by metazoans did not appear until the early Paleozoic. From then until the Recent, reefs diversified, underwent extinctions many times and then diversified again. Reef-inhabiting organisms included many different groups from algae to vertebrates as well as enigmatic, extinct suprageneric taxa. Evolution of these groups continued unabated and sometimes resulted in significant changes in the communities making up reefs. These reef groups varied over geologic time with extinction events commonly marking dramatic changes in the biotas. Paleozoic reefs consisted of sponges, corals, foraminifera, algae, bryozoans, and brachiopods, among others. The major extinction event at the end of the Paleozoic eliminated these forms as reef constituents and new groups (e.g., the first scleractinian corals) appeared in the Triassic. The Mesozoic was dominated by sponges, corals, rudist bivalves, and algae, most of which were eliminated in the end-Cretaceous extinction event. The Cenozoic reef biotas included red algae, foraminifera, sponges, corals, various invertebrates, and fish. Throughout the Phanerozoic, these biotas were eliminated by extinction events of differing magnitude. Each event corresponded to warming due to rising greenhouse gases (CO2 and CH4), and ocean acidification caused by lowered pH and anoxia of shallow waters that took severe tolls on reef organisms. These extinction events caused the decline of reef organisms and the reefs they built, resulting in decreased diversity and slower carbonate deposition. Photosymbiotic reef ecosystems failed during extinctions and these failures may have been driven, at least in part, by either the demise of the symbiosis or the extinction of symbionts. Reefs were generally absent in post-extinction times due to different ecologies. The
Science is so exciting! Why? Because it is awe-inspiring, fun, and creative. Most scientists woul... more Science is so exciting! Why? Because it is awe-inspiring, fun, and creative. Most scientists would not do anything else — they are truly dedicated to what they do. You can hardly get them to be quiet once they start talking about their work. Unlike most people, they usually love their jobs! However, this is not the common view presented of most scientists. They are commonly thought of as nerds, freaks, weirdoes, or evil-doers as portrayed in movies or television. These are fantasies where, with a few exceptions, scientists are shown negatively because it fits dramatic needs (Crichton, 1999). It's just not true in real life.
... When we see trash-science in the media, we should respond immediately with rational and intel... more ... When we see trash-science in the media, we should respond immediately with rational and intelligent commentary to the networks, sponsors ... But they didn't. This kind of misrepresentation on a powerful, pervasive medium like television is simply wrong and irresponsible. ...
The complex of historical events encompassing the origin and early evolution of Metazoa is at onc... more The complex of historical events encompassing the origin and early evolution of Metazoa is at once the salient feature and the most significant unresolved biohistorical phenomenon in the history of life. It has been the single most perplexing issue since paleontology emerged as a scientific discipline in the eighteenth and nineteenth centuries. Many of paleontology’s heroic figures (W. Buckland, C. Lyell, C. R. Darwin, C. D. Walcott) and modern leaders (P. E. Cloud, B. Runnegar, S. M. Stanley, J. W. Valentine) have offered hypotheses or scenarios to explain or account for events of this critical juncture in the history of life. To date, none of these ideas are widely accepted.
... Models of Calcification in Foraminifera ... . . ... Models of Calcification in Foraminifera C... more ... Models of Calcification in Foraminifera ... . . ... Models of Calcification in Foraminifera Calcification has been observed in foraminifera with walls of needle-like calcite (Miliolina) and sutured calcite (Rotaliina), but not in the spicular nor the microн granular (fossil) calcitic species. ...
Page 1. Journal of Foraminiferal Research, v. 4, no. 2, p. 80-85, April 1974 PLANKTONIC FORAMINIF... more Page 1. Journal of Foraminiferal Research, v. 4, no. 2, p. 80-85, April 1974 PLANKTONIC FORAMINIFERA ASSOCIATED WITH ANTARCTIC SEA ICE JERE H. LIPPS AND WILLIAM N. KREBS Department of Geology, University of California Davis, California 95616 ABSTRACT ...
Foraminifera inhabiting the muddy substrata within the coastal mangrove forests (Rhizophora stylo... more Foraminifera inhabiting the muddy substrata within the coastal mangrove forests (Rhizophora stylosa Griff.) on Moorea, French Polynesia, are distinct from other near shore foraminiferal assemblages around the island. Yet the mangroves were introduced from New Caledonia only in 1937 at Vaianahe Bay; they have since spread to many other sites around Moorea. They invade and occupy mud substrata below Paspalum marshes, the marshes themselves and mud under overhanging Hibiscus stands. The mangrove foraminifera cluster uniquely among themselves when compared to other lagoonal habitats, including those invaded by the mangroves. Thus, the introduction of mangroves has apparently allowed the development of a new community or assemblage of foraminifera. Mangrove foraminifera include Ammoastuta salsa, Ammotium tepida, Paratrochammina stoeni, Reophax cf. R. bacillaris, Trichohylus aguayoi, Trochammina inflata, and other subsidiary species of Ammonia, Elphidium, Quinqueloculina, Cornuspira, and Rosalina. Arenoparrellla mexicana, a characteristic species in mangroves elsewhere, is absent from Moorea, perhaps because it was never there like the mangroves themselves. The mangrove species cluster midway between those of shallow-water lagoonal mud, salt grass Paspalum marshes, and the muddy habitats below Hibiscus trees, even when they occur at similar elevations above or below sea level. The foraminifera in the unique cluster in the mangroves were not introduced with the initial mangrove trees, as the trees were established from propagules carried to the site by humans. The cluster is also found in other newer stands on the island that were colonized by floating propagules. The foraminiferal mangrove assemblage at Moorea is a more recent amalgamation of taxa recruited from the species pools in the associated salt grass Paspalum, Hibiscus and shallow-water lagoonal mud habitats. This recruitment happened quickly, most likely as soon as the mangroves grew to sufficient size to trap fine sediment and organic material, as these species are constantly transported about the lagoon chiefly by birds, rafts of algae or foam, and turbidity created by winds and storms. Some but not all foraminiferal species from these environments were able to occupy the new mangrove habitat. This indicates that the unique clusters of foraminifera have no biologic unity, but are simply associations of species that tolerate slightly different but similar environments at different elevations and with increased organic content, and with decreased wave action caused by mangrove roots. Previous studies of foraminiferal and other associations also indicate that in many situations marine organisms are not necessarily dependent on other specific species. Even in seemingly structured reef and rocky-shore communities with geologic histories of similar communities over thousands of years, the rapidity with which dispersal of larvae, eggs, or adult organisms takes place, and similar environmental conditions maintain this similarity of community, not principally any biologic dependence of species upon one another.
Three putative ciliate fossils were described from the Neoproterozoic Doushantuo Formation in Chi... more Three putative ciliate fossils were described from the Neoproterozoic Doushantuo Formation in China: Eotintinnopsis, Wujiangella, and Yonyangella. The identity of these fossils is important for our understanding of the origins and early morphological evolution within ciliate clades. Here we compare the homology of the fossil characteristics with those in their proposed ciliate relatives. Eotintinnopsis resembles a tintinnid, but its feathery tentacle-like apical structure is probably not homologous within any known ciliate. Wujiangella presents homology issues with the size and distribution of its putative somatic cilia. Yonyangella appears to be a suctorian with its tentaclelike structures, but the presence and size of its putative somatic cilia pose homology issues. We suggest that these three fossils are likely to be taphonomically and diagenetically distorted and altered acritarchs. These alterations include secondary mineral encrustations on the interiors of vesicles, the crushing, folding and other distortions of the vesicles, the bending and crushing of the acritarch spines, and the preservation of organic material in and outside of the cysts. The earliest known ciliate fossil remains a tintinnid that occurs in the Ordovician of Kazakhstan.
Perhaps no fossil group is used as much as foraminifera for paleoecologic inference, both in acad... more Perhaps no fossil group is used as much as foraminifera for paleoecologic inference, both in academia and industry. Since the late 1960s, new concepts and much additional data have appeared that make it difficult for the casual worker not immediately concerned with foraminiferal ecology and paleoecology to stay abreast of the latest developments. In these notes, the authors summarize much of that information, or provide reference to more detailed sources. They also attempt to point out problems and other methods of dealing with them. Most paleoecologic work with foraminifera in the past has relied on direct comparison of fossil assemblages with the most similar modern assemblages, and inferring then that the environments were similar also. The method is used widely in scientific studies and in industrial applications. The result is based on the single hypothesis that the fossils are environmentally analogous to their modern counterparts. These notes present a number of alternative working hypotheses, and in some cases, examine the data to attempt of disprove them.
Reef organisms are well known for engaging in photosymbiosis in which a heterotrophic protist or ... more Reef organisms are well known for engaging in photosymbiosis in which a heterotrophic protist or animal host partners with one or more kinds of photosynthetic microbes. This relationship provides metabolic advantages in nutrition and rapid calcification, often leading to secretion of massive skeletons in the host. In turn the symbiont receives protection, physical stability in the photic zone and direct access to the sun's energy. On an evolutionary scale, this relationship provided strong selective pressures for producing the algal-host relationship and has occurred multiple times in geological history. Today, different kinds of algae (dinoflagellates, diatoms, chlorophytes, rhodophytes, and cyanobacteria) inhabit various hosts (foraminifera, corals, mollusks) in modern reefs, and multiple phylogenetically separate algae may have also inhabited phylogenetically distinct ancient animals and protists. The modern dinoflagellate photosymbiont Symbiodinium occurs in a wide variety of unrelated host organisms from protists to mollusks. Molecular data indicate this genus first evolved either after the end-Cretaceous mass extinction 65 my ago or in the Early Eocene some 55 my ago. Encysted dinoflagellates related to Symbiodinium have been traced to the Triassic, and photosymbiosis may have been involved in even earlier reef associations. In all fossils, however, the identity of ancient photosymbionts is difficult to establish because they rarely, if ever, fossilize. Nevertheless, indirect evidence indicates that photosymbiotic ecosystems existed at least as far back as the Cambrian. Inferential lines of evidence, including large colony size, massive skeletons,
Although reef-like structures formed in the Neoproterozoic, reefs built by metazoans did not appe... more Although reef-like structures formed in the Neoproterozoic, reefs built by metazoans did not appear until the early Paleozoic. From then until the Recent, reefs diversified, underwent extinctions many times and then diversified again. Reef-inhabiting organisms included many different groups from algae to vertebrates as well as enigmatic, extinct suprageneric taxa. Evolution of these groups continued unabated and sometimes resulted in significant changes in the communities making up reefs. These reef groups varied over geologic time with extinction events commonly marking dramatic changes in the biotas. Paleozoic reefs consisted of sponges, corals, foraminifera, algae, bryozoans, and brachiopods, among others. The major extinction event at the end of the Paleozoic eliminated these forms as reef constituents and new groups (e.g., the first scleractinian corals) appeared in the Triassic. The Mesozoic was dominated by sponges, corals, rudist bivalves, and algae, most of which were eliminated in the end-Cretaceous extinction event. The Cenozoic reef biotas included red algae, foraminifera, sponges, corals, various invertebrates, and fish. Throughout the Phanerozoic, these biotas were eliminated by extinction events of differing magnitude. Each event corresponded to warming due to rising greenhouse gases (CO2 and CH4), and ocean acidification caused by lowered pH and anoxia of shallow waters that took severe tolls on reef organisms. These extinction events caused the decline of reef organisms and the reefs they built, resulting in decreased diversity and slower carbonate deposition. Photosymbiotic reef ecosystems failed during extinctions and these failures may have been driven, at least in part, by either the demise of the symbiosis or the extinction of symbionts. Reefs were generally absent in post-extinction times due to different ecologies. The
Science is so exciting! Why? Because it is awe-inspiring, fun, and creative. Most scientists woul... more Science is so exciting! Why? Because it is awe-inspiring, fun, and creative. Most scientists would not do anything else — they are truly dedicated to what they do. You can hardly get them to be quiet once they start talking about their work. Unlike most people, they usually love their jobs! However, this is not the common view presented of most scientists. They are commonly thought of as nerds, freaks, weirdoes, or evil-doers as portrayed in movies or television. These are fantasies where, with a few exceptions, scientists are shown negatively because it fits dramatic needs (Crichton, 1999). It's just not true in real life.
... When we see trash-science in the media, we should respond immediately with rational and intel... more ... When we see trash-science in the media, we should respond immediately with rational and intelligent commentary to the networks, sponsors ... But they didn't. This kind of misrepresentation on a powerful, pervasive medium like television is simply wrong and irresponsible. ...
The complex of historical events encompassing the origin and early evolution of Metazoa is at onc... more The complex of historical events encompassing the origin and early evolution of Metazoa is at once the salient feature and the most significant unresolved biohistorical phenomenon in the history of life. It has been the single most perplexing issue since paleontology emerged as a scientific discipline in the eighteenth and nineteenth centuries. Many of paleontology’s heroic figures (W. Buckland, C. Lyell, C. R. Darwin, C. D. Walcott) and modern leaders (P. E. Cloud, B. Runnegar, S. M. Stanley, J. W. Valentine) have offered hypotheses or scenarios to explain or account for events of this critical juncture in the history of life. To date, none of these ideas are widely accepted.
... Models of Calcification in Foraminifera ... . . ... Models of Calcification in Foraminifera C... more ... Models of Calcification in Foraminifera ... . . ... Models of Calcification in Foraminifera Calcification has been observed in foraminifera with walls of needle-like calcite (Miliolina) and sutured calcite (Rotaliina), but not in the spicular nor the microн granular (fossil) calcitic species. ...
Page 1. Journal of Foraminiferal Research, v. 4, no. 2, p. 80-85, April 1974 PLANKTONIC FORAMINIF... more Page 1. Journal of Foraminiferal Research, v. 4, no. 2, p. 80-85, April 1974 PLANKTONIC FORAMINIFERA ASSOCIATED WITH ANTARCTIC SEA ICE JERE H. LIPPS AND WILLIAM N. KREBS Department of Geology, University of California Davis, California 95616 ABSTRACT ...
Foraminifera inhabiting the muddy substrata within the coastal mangrove forests (Rhizophora stylo... more Foraminifera inhabiting the muddy substrata within the coastal mangrove forests (Rhizophora stylosa Griff.) on Moorea, French Polynesia, are distinct from other near shore foraminiferal assemblages around the island. Yet the mangroves were introduced from New Caledonia only in 1937 at Vaianahe Bay; they have since spread to many other sites around Moorea. They invade and occupy mud substrata below Paspalum marshes, the marshes themselves and mud under overhanging Hibiscus stands. The mangrove foraminifera cluster uniquely among themselves when compared to other lagoonal habitats, including those invaded by the mangroves. Thus, the introduction of mangroves has apparently allowed the development of a new community or assemblage of foraminifera. Mangrove foraminifera include Ammoastuta salsa, Ammotium tepida, Paratrochammina stoeni, Reophax cf. R. bacillaris, Trichohylus aguayoi, Trochammina inflata, and other subsidiary species of Ammonia, Elphidium, Quinqueloculina, Cornuspira, and Rosalina. Arenoparrellla mexicana, a characteristic species in mangroves elsewhere, is absent from Moorea, perhaps because it was never there like the mangroves themselves. The mangrove species cluster midway between those of shallow-water lagoonal mud, salt grass Paspalum marshes, and the muddy habitats below Hibiscus trees, even when they occur at similar elevations above or below sea level. The foraminifera in the unique cluster in the mangroves were not introduced with the initial mangrove trees, as the trees were established from propagules carried to the site by humans. The cluster is also found in other newer stands on the island that were colonized by floating propagules. The foraminiferal mangrove assemblage at Moorea is a more recent amalgamation of taxa recruited from the species pools in the associated salt grass Paspalum, Hibiscus and shallow-water lagoonal mud habitats. This recruitment happened quickly, most likely as soon as the mangroves grew to sufficient size to trap fine sediment and organic material, as these species are constantly transported about the lagoon chiefly by birds, rafts of algae or foam, and turbidity created by winds and storms. Some but not all foraminiferal species from these environments were able to occupy the new mangrove habitat. This indicates that the unique clusters of foraminifera have no biologic unity, but are simply associations of species that tolerate slightly different but similar environments at different elevations and with increased organic content, and with decreased wave action caused by mangrove roots. Previous studies of foraminiferal and other associations also indicate that in many situations marine organisms are not necessarily dependent on other specific species. Even in seemingly structured reef and rocky-shore communities with geologic histories of similar communities over thousands of years, the rapidity with which dispersal of larvae, eggs, or adult organisms takes place, and similar environmental conditions maintain this similarity of community, not principally any biologic dependence of species upon one another.
Three putative ciliate fossils were described from the Neoproterozoic Doushantuo Formation in Chi... more Three putative ciliate fossils were described from the Neoproterozoic Doushantuo Formation in China: Eotintinnopsis, Wujiangella, and Yonyangella. The identity of these fossils is important for our understanding of the origins and early morphological evolution within ciliate clades. Here we compare the homology of the fossil characteristics with those in their proposed ciliate relatives. Eotintinnopsis resembles a tintinnid, but its feathery tentacle-like apical structure is probably not homologous within any known ciliate. Wujiangella presents homology issues with the size and distribution of its putative somatic cilia. Yonyangella appears to be a suctorian with its tentaclelike structures, but the presence and size of its putative somatic cilia pose homology issues. We suggest that these three fossils are likely to be taphonomically and diagenetically distorted and altered acritarchs. These alterations include secondary mineral encrustations on the interiors of vesicles, the crushing, folding and other distortions of the vesicles, the bending and crushing of the acritarch spines, and the preservation of organic material in and outside of the cysts. The earliest known ciliate fossil remains a tintinnid that occurs in the Ordovician of Kazakhstan.
Perhaps no fossil group is used as much as foraminifera for paleoecologic inference, both in acad... more Perhaps no fossil group is used as much as foraminifera for paleoecologic inference, both in academia and industry. Since the late 1960s, new concepts and much additional data have appeared that make it difficult for the casual worker not immediately concerned with foraminiferal ecology and paleoecology to stay abreast of the latest developments. In these notes, the authors summarize much of that information, or provide reference to more detailed sources. They also attempt to point out problems and other methods of dealing with them. Most paleoecologic work with foraminifera in the past has relied on direct comparison of fossil assemblages with the most similar modern assemblages, and inferring then that the environments were similar also. The method is used widely in scientific studies and in industrial applications. The result is based on the single hypothesis that the fossils are environmentally analogous to their modern counterparts. These notes present a number of alternative working hypotheses, and in some cases, examine the data to attempt of disprove them.
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Papers by Jere Lipps