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Journal articles on the topic 'Gemmules'

Author: Grafiati
Published: 4 June 2021
Last updated: 10 February 2022

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1

PINHEIRO, ULISSES, LUDIMILA CALHEIRA, CELINA MARTINS, LIESL JANSON, RICKY TAYLOR, and TOUFIEK SAMAAI. "Two new species of freshwater sponges from Neotropical and Afrotropical Regions." Zootaxa 4728, no. 3 (January 23, 2020): 363–71. http://dx.doi.org/10.11646/zootaxa.4728.3.5.

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Geographic distributions of freshwater sponges are related to the geological and climatic history of the continents, on the presence of gemmules and the morphological complexity of this resistant body to withstand change. Gemmules are characteristic of the freshwater Families Spongillidae, Metaniidae and Potamolepidae. However, Acanthotylotra alvarengai, Echinospongilla brichardi and a number of other species within the genus Potamolepis do not produce gemmules. Potamolepis is endemic to the Afrotropical region with seven valid species. African freshwater sponges however, are mostly known from a single specimen (the holotype), due to the scarcity of material from these freshwater systems. In the present study, we describe two new species of non-gemmule bearing freshwater sponges from the Neotropical and Afrotropical Regions.
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2

Copeland, John E., Stan C. Kunigelis, Emily A. Stuart, and Kayleigh A. Hanson. "First Records of Freshwater Sponges (Porifera: Spongillidae) for Great Smoky Mountains National Park." Journal of the Tennessee Academy of Science 95, no. 1 (December 1, 2020): 59–62. http://dx.doi.org/10.47226/jtas-d-18-00004.

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Abstract A survey of four selected streams in the Tennessee portion of the Great Smoky Mountains National Park was conducted to document the presence of freshwater sponges. Streams were surveyed by wading and observing rock and log substrates for sponges. Sponges were viewed with a 10X magnifier for gemmules. If gemmules were present a portion of the sponge containing gemmules was collected. Scanning electron microscopy of gemmules and spicules was used for taxonomic identification. Two species, Radiospongilla crateriformis and Trochospongilla horrida, were discovered. Both were found in the Abrams Creek embayment of Chilhowee Lake. These findings represent the first records of freshwater sponges within the Great Smoky Mountains National Park.
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3

Ibraimov, A. I. "Darwin’s Gemmules and Development." Anthropologist 11, no. 1 (January 2009): 1–5. http://dx.doi.org/10.1080/09720073.2009.11891071.

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4

Liu, Y. S. "Darwin’s gemmules and oncogenes." Annals of Oncology 21, no. 4 (April 2010): 908. http://dx.doi.org/10.1093/annonc/mdp608.

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5

Bart, Martijn C., Sebastiaan J. de Vet, Didier M. de Bakker, Brittany E. Alexander, Dick van Oevelen, E. Emiel van Loon, Jack J. W. A. van Loon, and Jasper M. de Goeij. "Spiculous skeleton formation in the freshwater sponge Ephydatia fluviatilis under hypergravity conditions." PeerJ 6 (January 4, 2019): e6055. http://dx.doi.org/10.7717/peerj.6055.

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Successful dispersal of freshwater sponges depends on the formation of dormant sponge bodies (gemmules) under adverse conditions. Gemmule formation allows the sponge to overcome critical environmental conditions, for example, desiccation or freezing, and to re-establish as a fully developed sponge when conditions are more favorable. A key process in sponge development from hatched gemmules is the construction of the silica skeleton. Silica spicules form the structural support for the three-dimensional filtration system the sponge uses to filter food particles from ambient water. We studied the effect of different hypergravity forces (1, 2.5, 5, 10, and 20 × g for 48 h)—as measure for environmental stress—on the ability of developing sponges to set-up their spiculous skeleton. Additionally, we assessed whether the addition of nutrients (i.e., dissolved 13C- and 15N-labeled amino acids) compensates for this stress. Our results show that freshwater sponges can withstand prolonged periods of hypergravity exposure and successfully set-up their skeleton, even after 48 h under 20 × g. Developing sponges were found to take up and assimilate dissolved food before forming a functional filtering system. However, fed and non-fed sponges showed no differences in skeleton formation and relative surface area growth, suggesting that the gemmules’ intrinsic energy fulfills the processes of skeleton construction. Additionally, non-fed sponges formed oscula significantly more often than fed sponges, especially under higher g-forces. This suggests that the eventual formation of a filtration system might be stimulated by food deprivation and environmentally stressful conditions. These findings indicate that the process of spiculous skeleton formation is energy-efficient and highly resilient. The uptake of dissolved food substances by freshwater sponges may contribute to the cycling of dissolved organic matter in freshwater ecosystems where sponges are abundant.
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6

Boutselis, N. J., P. E. Fell, and S. H. Loomis. "Cold tolerance of sponge gemmules." Cryobiology 26, no. 6 (December 1989): 549. http://dx.doi.org/10.1016/0011-2240(89)90119-3.

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7

Turner, Judith. "Sponge Gemmules from Lake Sediments in the Puget Lowland, Washington." Quaternary Research 24, no. 2 (July 1985): 240–43. http://dx.doi.org/10.1016/0033-5894(85)90010-9.

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Gemmules of five species of freshwater sponge found in deposits at Cedar Mountain bog in the southeastern Puget Lowland were used to infer that during the late-glacial period the water was calcareous, was not deficient in SiO2, was aerobic, and had a pH in the range 6.6–8.5. This is consistent with plant fossil data. In view of their paleoenvironmental potential it is worth looking for gemmules when extracting other fossils from lake sediments.
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8

Liu, Yongsheng. "Circulating nucleic acids and Darwin's gemmules." Expert Opinion on Biological Therapy 12, sup1 (April 21, 2012): S225—S226. http://dx.doi.org/10.1517/14712598.2012.680589.

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9

Reiswig, Henry M., and Tanya L. Miller. "Freshwater Sponge Gemmules Survive Months of Anoxia." Invertebrate Biology 117, no. 1 (1998): 1. http://dx.doi.org/10.2307/3226846.

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10

ILAN, MICHA, GAL DEMBO, and AVITAL GASITH. "Gemmules of sponges from a warm lake." Freshwater Biology 35, no. 1 (February 1996): 165–72. http://dx.doi.org/10.1046/j.1365-2427.1996.00486.x.

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11

MANCONI, R., T. CUBEDDU, and R. PRONZATO. "Australian freshwater sponges with a new species of Pectispongilla (Porifera: Demospongiae: Spongillida)." Zootaxa 4196, no. 1 (November 20, 2016): 61. http://dx.doi.org/10.11646/zootaxa.4196.1.3.

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This paper focus on the biodiversity assessment of Australian inland water. Checklists of Australian Spongillida are also provided with biogeographic notes together with the geographic range of all species of freshwater sponges in Australia. New discoveries on freshwater sponges are reported from ephemeral freshwater habitats in Kakadu National Park (Australia Northern Territory). Morphological analyses show that the sponges belong to Radiospongilla and Pectispongilla in the family Spongillidae. Radiospongilla cfr. philippinensis shows a single layer of radial gemmuloscleres and the absence of tangential gemmuloscleres in the gemmular theca. Pectispongilla gagudjuensis n. sp. diverges from the diagnostic traits of the four species currently assigned to the genus i.e. skeletal megascleres are dominant acanthostrongyles and less frequent acanthoxeas shorter than in the other species, microscleres are absent, and gemmules are larger than in the other species of the genus.
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12

Boutselis, Nicholas J., Paul E. Fell, and Stephen H. Loomis. "Low temperature tolerance of the gemmules ofEunapius fragilis." Journal of Experimental Zoology 255, no. 1 (July 1990): 125–29. http://dx.doi.org/10.1002/jez.1402550117.

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13

MANCONI, RENATA, and ROBERTO PRONZATO. "The genus Corvospongilla Annandale, 1911 (Porifera: Demospongiae: Spongillida) from Madagascar freshwater with description of a new species: biogeographic and evolutionary aspects." Zootaxa 4612, no. 4 (May 31, 2019): 544. http://dx.doi.org/10.11646/zootaxa.4612.4.6.

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We report here the first record of five genera of Spongillida (Porifera, Demospongiae) in both lentic and lotic water of Madagascar and the discovery of a new species of the genus Corvospongilla from the Betsiboka River hydrographic basin. Corvospongilla lemuriensis sp. n. diverges from all the other known species of the genus in its unique combination of diagnostic morphotraits (a) sessile gemmules with chambered pneumatic layer within tri-layered theca and enveloped by spicular cage of dominant acanthostrongyles, (b) dominant acanthostrongyles and less frequent acanthoxeas-strongyloxeas as megascleres and gemmuloscleres. The new species is characterised by the exclusive presence of a well-developed pneumatic layer in sessile gemmules not described for the genus until now. The new record confirms a Gondwanian track for the genus Corvospongilla and increases the knowledge on Spongillida historical biogeography. In synthesis the present discovery of Corvospongilla in the Malagasy biogeographic province (a) contributes to the assessment of Afrotropical biodiversity, (b) enlarges the geographic range of the genus reducing its disjunct distribution, and (c) focus on the evolutionary history of adaptive morphofunctional traits of resting bodies and life cycle timing in ephemeral water of the south-eastern Austral hemisphere.
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14

Fell, Paul E., and Allison E. Fell. "Cold Hardiness of the Gemmules of Eunapius fragilis (Porifera: Spongillidae)." Transactions of the American Microscopical Society 106, no. 2 (April 1987): 187. http://dx.doi.org/10.2307/3226319.

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15

Kuzawa, C. "Response to Liu and Li: In defence of gemmules: really?" International Journal of Epidemiology 41, no. 5 (October 1, 2012): 1493–94. http://dx.doi.org/10.1093/ije/dys133.

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16

MATTEUZZO, MARCELA C., CECÍLIA VOLKMER-RIBEIRO, ANGÉLICA F. D. C. VARAJÃO, CÉSAR A. C. VARAJÃO, ANNE ALEXANDRE, DEMETRIO L. GUADAGNIN, and ARIANA C. S. ALMEIDA. "Environmental factors related to the production of a complex set of spicules in a tropical freshwater sponge." Anais da Academia Brasileira de Ciências 87, no. 4 (November 27, 2015): 2013–29. http://dx.doi.org/10.1590/0001-3765201520140461.

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ABSTRACT Adverse natural conditions will, generally, induce gemmulation in freshwater sponges. Because of this environmental dependence, gemmoscleres are given exceptional value in taxonomic, ecological and paleoenvironmental studies. Other spicules categories such as microscleres and beta megascleres have received little attention with regard to their occurrence and function during the sponge biological cycle. Metania spinata, a South American species common to bog waters in the Cerrado biome, produces alpha and beta megascleres, microscleres and gemmoscleres. To detect the environmental factors triggering the production of all these kinds of spicules, the species annual seasonal cycle was studied. Artificial substrates were devised, supplied with gemmules and placed in Lagoa Verde pond which contained a natural population of M. spinata. Field monitoring was conducted for eight months in order to observe the growth of sponges and spicules formation. Samples of water were taken monthly for physical and chemical parameters determination. The appearance of the alpha megascleres was sequentially followed by that of microscleres, gemmoscleres and beta megascleres. The first ones built the new sponge skeleton, the last three were involved in keeping inner moisture in the sponge body or its gemmules. The water level, temperature and the silicon (Si) concentration in the pond were the most important factors related to this sequential production of spicules, confirming environmental reconstructions based on the presence or absence of alpha megascleres and gemmoscleres in past sediments.
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17

Machado, Vanessa de Souza, Cecília Volkmer-Ribeiro, and Roberto Iannuzzi. "First record of preserved gemmules of a Pleistocene assemblage of freshwater sponges." Revista Brasileira de Paleontologia 16, no. 2 (August 30, 2013): 169–80. http://dx.doi.org/10.4072/rbp.2013.2.01.

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18

Ungemach, Louis F., Kerry Souza, Paul E. Fell, and Stephen H. Loomis. "Possession and Loss of Cold Tolerance by Sponge Gemmules: A Comparative Study." Invertebrate Biology 116, no. 1 (1997): 1. http://dx.doi.org/10.2307/3226918.

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19

Fell, Paul E., and Erika D. Levasseur. "Cold hardiness of the green gemmules of Spongilla lacustris L. (Porifera: Spongillidae)." Hydrobiologia 218, no. 2 (July 1991): 107–12. http://dx.doi.org/10.1007/bf00006783.

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20

Calheira, Ludimila, Emilio Lanna, and Ulisses Pinheiro. "Tropical freshwater sponges develop from gemmules faster than their temperate-region counterparts." Zoomorphology 138, no. 4 (August 16, 2019): 425–36. http://dx.doi.org/10.1007/s00435-019-00458-0.

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21

Choi, Youngeun, and Susan E. Mango. "Hunting for Darwin's gemmules and Lamarck's fluid: Transgenerational signaling and histone methylation." Biochimica et Biophysica Acta (BBA) - Gene Regulatory Mechanisms 1839, no. 12 (December 2014): 1440–53. http://dx.doi.org/10.1016/j.bbagrm.2014.05.011.

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22

Du, Wei, Xun Lian Wang, and Tsuyoshi Komiya. "Potential Ediacaran sponge gemmules from the Yangtze Gorges area in South China." Gondwana Research 28, no. 3 (October 2015): 1246–54. http://dx.doi.org/10.1016/j.gr.2014.08.012.

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23

Deichmann, Ute. "Gemmules and Elements: On Darwin’s and Mendel’s Concepts and Methods in Heredity." Journal for General Philosophy of Science 41, no. 1 (June 2010): 85–112. http://dx.doi.org/10.1007/s10838-010-9122-0.

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24

Rueda, Juan, and Francesc Mesquita-Joanes. "New contributions to the knowledge of freshwater macro­invertebrates of Costa Rica and Nicaragua, with particular focus on sponges." Anales de Biología, no. 40 (February 21, 2018): 9–20. http://dx.doi.org/10.6018/analesbio.40.02.

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Se estudia la caracterización limnológica de 30 lagunas del bosque tropical seco de Costa Rica y Nicaragua durante 2010-11. Se aislaron gémulas de esponjas de agua dulce en cuatro de las localidades. Se registraron dos nuevas citas de esponjas para Nicaragua, Radiospongilla cerebellata (Bowerbank, 1863) y Corvoheteromeyenia heterosclera (Ezcurra de Drago, 1974). En Costa Rica también se registró esta última y se recolectaron ejemplares de Radiospongilla crateriformis (Potts, 1882). En otra laguna de Costa Rica, se recolectó una larva neuróptero (Insecta) de la familia Sisyridae asociada a las esponjas: Sisyra apicalis Banks, 1908. Por otro lado, hemos podido recolectar gémulas incrustadas en el tubo de alojamiento del oligoqueto Aulophorus vagus Leidy, 1880 (Annelida: Oligochaeta: Naididae), que también supone la primera cita para Costa Rica y Nicaragua. The characterization of 30 temporary ponds was done in the tropical dry forest of Costa Rica and Nicaragua, in 2010-2011. Gemmules of sponges were isolated in four of the studied sites. Two new records were set for Nicaragua, Radiospongilla cerebellata (Bowerbank, 1863) and Corvoheteromeyenia heterosclera (Ezcurra de Drago, 1974). In Costa Rica, the last ones was also recorded as well as specimens of Radiospongilla crateriformis (Potts, 1882) were collected. In another pond of Costa Rica, larva of Neuroptera (Insecta) belonging to family Sisyridae, commonly associated to sponges, was collected: Sisyra apicalis Banks, 1908. In addition, we have been able to collect embedded gemmules in the housing tube of the annelid Aulophorus vagus Leidy, 1880 (Annelida: Oligochaeta: Naididae). This species is also here reported for the first time in Costa Rica and Nicaragua.
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25

Volkmer-Ribeiro, Cecilia, Maria da Conceição M. Tavares, and Karina Fürstenau de Oliveira. "Acanthotylotra alvarengai (Porifera, Demospongiae) new genus and species of sponge from Tocantins river, Pará State, Brazil." Iheringia. Série Zoologia 99, no. 4 (December 2009): 345–48. http://dx.doi.org/10.1590/s0073-47212009000400002.

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Acanthotylotra a new monotypic genus of freshwater sponge is defined. Its sole species A. alvarengai sp. nov. is described based upon microscopic specimens recovered from the Tocantins river, Pará State, Brazil, when the deep rocky substrate was temporarily exposed downstream from the dam at the time it was closed for lake formation. A unique set of megascleres, allied to the paucity of spongin, the renieroid skeleton and the fact that gemmules or new specimens remain undetected, call for the proposition of a new monospecific genus to be retained as incertae sedis until new larger and probably gemmuliferous specimens come to be found.
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26

Barbeau, M. A., H. M. Reiswig, and L. C. Rath. "Hatching of freshwater sponge gemmules after low temperature exposure: Ephydatia mülleri (Porifera: Spongillidae)." Journal of Thermal Biology 14, no. 4 (October 1989): 225–31. http://dx.doi.org/10.1016/0306-4565(89)90009-0.

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27

Liu, Yongsheng, and Xiuju Li. "Darwin and Mendel today: a comment on “Limits of imagination: the 150th Anniversary of Mendel’s Laws, and why Mendel failed to see the importance of his discovery for Darwin’s theory of evolution”." Genome 59, no. 1 (January 2016): 75–77. http://dx.doi.org/10.1139/gen-2015-0155.

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We comment on a recent paper by Rama Singh, who concludes that Mendel deserved to be called the father of genetics, and Darwin would not have understood the significance of Mendel’s paper had he read it. We argue that Darwin should have been regarded as the father of genetics not only because he was the first to formulate a unifying theory of heredity, variation, and development — Pangenesis, but also because he clearly described almost all genetical phenomena of fundamental importance, including what he called “prepotency” and what we now call “dominance” or “Mendelian inheritance”. The word “gene” evolved from Darwin’s imagined “gemmules”, instead of Mendel’s so-called “factors”.
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28

Loomis, S. H., L. F. Ungemach, B. R. Branchini, S. C. Hand, and P. E. Fell. "Carbohydrate Mobilization During Germination of Post-Diapausing Gemmules of the Freshwater Sponge Eunapius fragilis." Biological Bulletin 191, no. 3 (December 1996): 393–401. http://dx.doi.org/10.2307/1543012.

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29

Fell, Paul E. "Influences of Temperature and Desiccation on Breaking Diapause in the Gemmules ofEunapius fraqilis(Leidy)." International Journal of Invertebrate Reproduction and Development 11, no. 3 (May 1987): 305–15. http://dx.doi.org/10.1080/01688170.1987.10510289.

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30

NICACIO, GILBERTO, WILLIAM SEVERI, and ULISSES PINHEIRO. "New species of Radiospongilla (Porifera: Spongillidae) from Brazilian inland waters." Zootaxa 3132, no. 1 (December 15, 2011): 56. http://dx.doi.org/10.11646/zootaxa.3132.1.2.

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Radiospongilla Penney & Racek, 1968, characterized by gemmoscleres radially arranged on gemmules and absence of microscleres, is widely distributed in the world across all zoogeographical regions except for Antarctica. In the Neotropical Region only two species are known so far: R. crateriformis (Potts, 1882) and R. amazonensis Volkmer-Ribeiro & Maciel, 1983. Here we describe a new species of Radiospongilla, R. inesi sp. nov., from 28 specimens collected between May 2007 to April 2010 from channels and ponds at the Aquaculture Station of Universidade Federal Rural de Pernambuco, Rio do Prata Basin, Recife, Pernambuco State, Brazil. This new species differs from other species of Radiospongilla from South America in the morphology of its megascleres and gemmoscleres.
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31

Loomis, S. H., S. C. Hand, and P. E. Fell. "Metabolism of Gemmules From the Freshwater Sponge Eunapius fragilis During Diapause and Post-Diapause States." Biological Bulletin 191, no. 3 (December 1996): 385–92. http://dx.doi.org/10.2307/1543011.

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32

Jetton, Thomas L., Paul E. Fell, and Frederick W. Harrison. "Cytological and cytochemical investigations of development from dormant gemmules of the marine sponge,Haliclona loosanoffi." Journal of Morphology 193, no. 1 (July 1987): 99–116. http://dx.doi.org/10.1002/jmor.1051930110.

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33

BAZER, LAURENCE J., and PAUL E. FELL. "Gemmules of Anheteromeyenia ryderi and Heteromeyenia tubisperma (Porifera: Spongillidae) from southern New England undergo diapause." Freshwater Biology 16, no. 4 (August 1986): 479–84. http://dx.doi.org/10.1111/j.1365-2427.1986.tb00990.x.

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34

SHIMADA, ATSUKO, and NOBUO EGAMI. "Comparison of the radiosensitivity of dry dormant eggs, gemmules, and statoblasts of three invertebrate forms." Journal of Radiation Research 26, no. 1 (1985): 123–30. http://dx.doi.org/10.1269/jrr.26.123.

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35

Cândido, Jairo Luís, Cecília Volkmer-Ribeiro, and Karina Fürstenau-Oliveira. "Dosilia (Porifera, Demospongiae) redefined." Iheringia. Série Zoologia 100, no. 4 (December 2010): 425–48. http://dx.doi.org/10.1590/s0073-47212010000400017.

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Dosilia plumosa (Carter, 1849), type species of the genus, and D. brouni (Kirkpatrick, 1906), with distribution respectively in the Oriental and Ethiopic regions, are revised based on a SEM analysis of spicules, gemmules and skeletal structure. The lectotype here designated for D. plumosa is illustrated as well as the holotype by monotypy determined for D. brouni. Dosilia palmeri (Potts, 1885) and D. radiospiculata (Mills, 1888) distributed in the Nearctic and Neotropical regions and D. pydanieli Volkmer-Ribeiro, 1992, found in the Neotropical region, are revised based on a SEM analysis of spicules, gemules and skeletal structure. The holotype by monotypy is determined for D. radiospiculata. Heteromeyenia plumosa Weltner,1895 is synonymyzed with D. radiospiculata. Upon the revision of its five species, the genus is redefined and a key presented.
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36

Fell, Paul E., and Laurence J. Bazer. "Survival of the gemmules of Anheteromeyenia ryderi (Potts) following aerial exposure during winter in New England." Hydrobiologia 190, no. 3 (February 1990): 241–46. http://dx.doi.org/10.1007/bf00008191.

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37

Pisera, Andrzej, Klaus Rützler, Józef Kaz'mierczak, and Stephan Kempe. "Sponges in an extreme environment: suberitids from the quasi-marine Satonda Island crater lake (Sumbawa, Indonesia)." Journal of the Marine Biological Association of the United Kingdom 90, no. 1 (November 3, 2009): 203–12. http://dx.doi.org/10.1017/s0025315409990968.

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Sponges are rare in extreme environments, and very little is known about their adaptations to such settings. Evidence from two species in a marine-derived midwater stratified crater lake on Satonda Island (Sumbawa, Indonesia) suggests their production of gemmules (resting bodies), a rare trait in marine sponges but common in freshwater forms, may be a survival mechanism in the lake's harsh environment. With its epilimnion hydrochemistry—characterized by changing alkalinity, salinity, and O2 levels over the region's wet and dry seasons—the lake sustains only a few marine macroscopic organisms, among them the suberitid sponges Protosuberites lacustris comb. nov. and Suberites sp. (Hadromerida: Suberitida). Both species belong to the same group as sponges reported from other marine-derived lakes with strongly varying and extreme environmental (especially chemical) parameters. The morphological characters, taxonomic position, ecological adaptations, environmental conditions, and biota associated with the sponges in this ecologically unique site are presented here.
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38

Petit, Gilles, and Sylvain Charbonnier. "Fossil sponge gemmules, epibionts ofCarpopenaeus garassinoin. sp. (Crustacea, Decapoda) from the Sahel Alma Lagerstätte (Late Cretaceous, Lebanon)." Geodiversitas 34, no. 2 (June 2012): 359–72. http://dx.doi.org/10.5252/g2012n2a6.

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39

Weissenfels, Norbert. "The influence of an eucaryotic intranuclear cell parasite on the production of gemmules inEphydatia fluviatilis (Porifera, Spongillidae)." Zoomorphology 111, no. 4 (December 1992): 207–16. http://dx.doi.org/10.1007/bf01633009.

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40

Fell, Paul E. "Salinity tolerance of the gemmules of Eunapius fragilis (Leidy) and the inhibition of germination by various salts." Hydrobiologia 242, no. 1 (September 1992): 33–39. http://dx.doi.org/10.1007/bf00017641.

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41

Noble, Denis. "The Illusions of the Modern Synthesis." Biosemiotics 14, no. 1 (March 26, 2021): 5–24. http://dx.doi.org/10.1007/s12304-021-09405-3.

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AbstractThe Modern Synthesis has dominated biology for 80 years. It was formulated in 1942, a decade before the major achievements of molecular biology, including the Double Helix and the Central Dogma. When first formulated in the 1950s these discoveries and concepts seemed initially to completely justify the central genetic assumptions of the Modern Synthesis. The Double Helix provided the basis for highly accurate DNA replication, while the Central Dogma was viewed as supporting the Weismann Barrier, so excluding the inheritance of acquired characteristics. This article examines the language of the Modern Synthesis and reveals that it is based on four important misinterpretations of what molecular biology had shown, so forming the basis of the four Illusions: 1. Natural Selection; 2. The Weismann Barrier; 3. The Rejection of Darwin’s Gemmules; 4. The Central Dogma. A multi-level organisation view of biology avoids these illusions through the principle of biological relativity. Molecular biology does not therefore confirm the assumptions of the Modern Synthesis.
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42

Volkmer-Ribeiro, Cecília, Maria da Conceição Tavares-Frigo, Alexandre Cunha Ribeiro, and Maria Elina Bichuette. "Arinosaster patriciae (Porifera, Demospongiae): new genus and species and the second record of a cave freshwater sponge from Brazil." Neotropical Biology and Conservation 16, no. 1 (January 19, 2021): 45–57. http://dx.doi.org/10.3897/neotropical.16.e50156.

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Arinosaster patriciae gen. nov. et sp. nov. is the second continental sponge registered for a subterranean environment (cave habitat) in Brazil and the Neotropical Region. The sponges were recorded and collected in a 5m depth technical dive in a sinkhole of Rio Claro, tributary of Rio Arinos, Tapajós system, Amazon Basin (-13.8170386, -56.6914225) at the locality of Sumidouro do Rio Claro, Municipality of Diamantino, state of Mato Grosso, central western Brazil. The cave is placed in sandstone rocks of the Parecis Group (Upper Cretaceous). “In situ” photographs of colonies, of living specimens, SEM illustrations of dissociated spicules as well as of the skeletal structure, are presented. The occurrence of euaster microscleres of the type spherasters are for the first time reported for continental sponges but, also new, is the occurrence of spongin fibers, composing with fibers of silicious spicules in the skeletal arrangement. The absence of gemmules in the studied material and the fact that new specimens remain undetected call for the proposition of a new monospecific genus to be retained as Incertae Sedis until new and gemmuliferous colonies are found.
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43

Loomis, Stephen H., Aubrey Bettridge, and Bruce R. Branchini. "The Effects of Elevated Osmotic Concentration on Control of Germination in the Gemmules of Freshwater Sponges Eunapius fragilis and Anheteromeyania ryderi." Physiological and Biochemical Zoology 82, no. 4 (July 2009): 388–95. http://dx.doi.org/10.1086/589901.

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44

Jakhalekar, Shriraj S., and H. V. Ghate. "SEM study of gemmules and spicules of Indian Trochospongilla latouchiana Annandale and Chinese T. latouchiana sinensis Annandale (Porifera: Demospongiae: Spongillina: Spongillidae)." Journal of Threatened Taxa 6, no. 9 (August 26, 2014): 6269–77. http://dx.doi.org/10.11609/jott.o4003.6269-77.

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45

Stürzenbaum, S. R., J. Andre, P. Kille, and A. J. Morgan. "Earthworm genomes, genes and proteins: the (re)discovery of Darwin's worms." Proceedings of the Royal Society B: Biological Sciences 276, no. 1658 (December 16, 2008): 789–97. http://dx.doi.org/10.1098/rspb.2008.1510.

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Small incremental biological change, winnowed by natural selection over geological time scales to produce large consequences, was Darwin's singular insight that revolutionized the life sciences. His publications after 1859, including the ‘earthworm book’, were all written to amplify and support the evolutionary theory presented in the Origin . Darwin was unable to provide a physical basis for the inheritance of favoured traits because of the absence of genetic knowledge that much later led to the ‘modern synthesis’. Mistaken though he was in advocating systemic ‘gemmules’ as agents of inheritance, Darwin was perceptive in seeking to underpin his core vision with concrete factors that both determine the nature of a trait in one generation and convey it to subsequent generations. This brief review evaluates the molecular genetic literature on earthworms published during the last decade, and casts light on the specific aspects of earthworm evolutionary biology that more or less engaged Darwin: (i) biogeography, (ii) species diversity, (iii) local adaptations and (iv) sensitivity. We predict that the current understanding will deepen with the announcement of a draft earthworm genome in Darwin's bicentenary year, 2009. Subsequently, the earthworm may be elevated from the status of a soil sentinel to that elusive entity, an ecologically relevant genetic model organism.
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46

Hall, Chelsea, Sara Camilli, Henry Dwaah, Benjamin Kornegay, Christie Lacy, Malcolm S. Hill, and April L. Hill. "Freshwater sponge hosts and their green algae symbionts: a tractable model to understand intracellular symbiosis." PeerJ 9 (February 11, 2021): e10654. http://dx.doi.org/10.7717/peerj.10654.

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In many freshwater habitats, green algae form intracellular symbioses with a variety of heterotrophic host taxa including several species of freshwater sponge. These sponges perform important ecological roles in their habitats, and the poriferan:green algae partnerships offers unique opportunities to study the evolutionary origins and ecological persistence of endosymbioses. We examined the association betweenEphydatia muelleriand its chlorophyte partner to identify features of host cellular and genetic responses to the presence of intracellular algal partners.Chlorella-like green algal symbionts were isolated from field-collected adultE. muelleritissue harboring algae. The sponge-derived algae were successfully cultured and subsequently used to reinfect aposymbioticE. muelleritissue. We used confocal microscopy to follow the fate of the sponge-derived algae after inoculating algae-freeE. muellerigrown from gemmules to show temporal patterns of symbiont location within host tissue. We also infected aposymbioticE. muelleriwith sponge-derived algae, and performed RNASeq to study differential expression patterns in the host relative to symbiotic states. We compare and contrast our findings with work in other systems (e.g., endosymbioticHydra) to explore possible conserved evolutionary pathways that may lead to stable mutualistic endosymbioses. Our work demonstrates that freshwater sponges offer many tractable qualities to study features of intracellular occupancy and thus meet criteria desired for a model system.
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47

Fell, Paul E. "Deep Diapause and the Influence of Low Temperature on the Hatching of the Gemmules of Spongilla lacustris (L.) and Eunapius fragilis (Leidy)." Invertebrate Biology 114, no. 1 (1995): 3. http://dx.doi.org/10.2307/3226947.

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48

Schill, Ralph O., Martin Pfannkuchen, Gisela Fritz, Heinz-r. Köhler, and Franz Brümmer. "Quiescent gemmules of the freshwater sponge,Spongilla lacustris (Linnaeus, 1759), contain remarkably high levels of Hsp70 stress protein andhsp70 stress gene mRNA." Journal of Experimental Zoology Part A: Comparative Experimental Biology 305A, no. 5 (May 1, 2006): 449–57. http://dx.doi.org/10.1002/jez.a.281.

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49

Reiswig, Henry M., and Anthony Ricciardi. "Reexamination of Corvospongilla novaeterrae (Porifera, Spongillidae), an environmentally restricted freshwater sponge from eastern Canada." Canadian Journal of Zoology 71, no. 10 (October 1, 1993): 1954–62. http://dx.doi.org/10.1139/z93-279.

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Corvospongilla novaeterrae (Potts, 1886) (Demospongiae, Spongillidae) is known only from a few acidic lakes on the eastern coast of Canada. It is considered by some to be a sexual hybrid and thus an invalid species. This assumption is based upon an erroneous interpretation of C. novaeterrae's highly variable gemmoscleres and the abundant of foreign spicules (predominantly those of Duosclera mackayi) in the type specimens. We have examined a new specimen from Nova Scotia that has no foreign spicules and fits the original species description. We evaluate three hypotheses concerning this species' status: (1) it is a hybrid of Corvomeyenia everetti and another species; (2) it is an unusual ecomorphic form of C. everetti resulting from atmospheric inputs of sea salts; (3) it is a valid Corvospongilla species, closely related to C. seckti, C. volkmeri, and C. boehmi. Corvospongilla novaeterrae's morphologically variable gemmoscleres are quite similar to those of C. seckti, C. volkmeri, and C. boehmi, and appear to be evolutionary transients between birotulates and amphioxea (as in Radiospongilla and Pectispongilla). Other characters linking C. novaeterrae with other Corvospongilla species include (i) large gemmules (diameter > 1000 μm) with simple multiple foramina, (ii) a weakly developed or absent pneumatic layer, (iii) the size and shape of the birotulate microscleres, and (iv) the predominantly rod-shaped, tangentially arranged gemmoscleres. Evidence supports the acceptance of C. novaeterrae as a valid, environmentally restricted species.
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50

Vilanova, Eduardo, Priscilla J. Ciodaro, Francisco F. Bezerra, Gustavo R. C. Santos, Juan J. Valle-Delgado, Dario Anselmetti, Xavier Fernàndez-Busquets, and Paulo A. S. Mourão. "Adhesion of freshwater sponge cells mediated by carbohydrate–carbohydrate interactions requires low environmental calcium." Glycobiology 30, no. 9 (February 20, 2020): 710–21. http://dx.doi.org/10.1093/glycob/cwaa014.

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Abstract Marine ancestors of freshwater sponges had to undergo a series of physiological adaptations to colonize harsh and heterogeneous limnic environments. Besides reduced salinity, river-lake systems also have calcium concentrations far lower than seawater. Cell adhesion in sponges is mediated by calcium-dependent multivalent self-interactions of sulfated polysaccharide components of membrane-bound proteoglycans named aggregation factors. Cells of marine sponges require seawater average calcium concentration (10 mM) to sustain adhesion promoted by aggregation factors. We demonstrate here that the freshwater sponge Spongilla alba can thrive in a calcium-poor aquatic environment and that their cells are able to aggregate and form primmorphs with calcium concentrations 40-fold lower than that required by marine sponges cells. We also find that their gemmules need calcium and other micronutrients to hatch and generate new sponges. The sulfated polysaccharide purified from S. alba has sulfate content and molecular size notably lower than those from marine sponges. Nuclear magnetic resonance analyses indicated that it is composed of a central backbone of non- and 2-sulfated α- and β-glucose units decorated with branches of α-glucose. Assessments with atomic force microscopy/single-molecule force spectroscopy show that S. alba glucan requires 10-fold less calcium than sulfated polysaccharides from marine sponges to self-interact efficiently. Such an ability to retain multicellular morphology with low environmental calcium must have been a crucial evolutionary step for freshwater sponges to successfully colonize inland waters.
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