41 posts · 26,628 views
I used to tutor biology and opened up this blog to post interesting stuff that I couldn't cover during the lesson time. I decided to keep it open and make random posts (= whatever strikes my fancy, requests by friends/e-mailers), all for the purpose of general education. Most of the posts are meant to introduce fundamental concepts or just describe the basics of a topic.
Marc
41 posts
Sort by: Latest Post, Most Popular
View by: Condensed, Full
- June 17, 2013
- 05:35 AM
- 36 views
How did sauropods get blood up their necks?
by Marc in Teaching Biology
Sauropods are the largest animals to have ever lived, surpassing whales even though they lived on land. Their unique anatomy, including their extremely long neck, has long been the subject of speculation and study, as their physiology must have stretched the limits of regular vertebrate capabilities. The topic of circulation is one central issue: how […]... Read more »
Seymour, R. (2009) Raising the sauropod neck: it costs more to get less. Biology Letters, 5(3), 317-319. DOI: 10.1098/rsbl.2009.0096
- September 13, 2012
- 10:30 AM
- 209 views
Wolbachia: The Ubiquitous Male-Killing, Feminising Parasite
by Marc in Teaching Biology
I mentioned Wolbachia in my parthenogenesis post; here I will talk about it in more detail, because it’s a really cool parasite, as well as in the center of much research nowadays. Index: Introduction Parasitism Transfer Biocontrol Positive Effects of Wolbachia Evolutionary Theory Practical Problems References Introduction Wolbachia are Gram-negative ⍺-Proteobacteria (order Rickettsiales, family Anaplasmataceae; [...]... Read more »
R. Stouthamer, J. A. J. Breeuwer, & G. D. D. Hurst. (1999) WOLBACHIA PIPIENTIS: Microbial Manipulator of Arthropod Reproduction. Annual Review of Microbiology. DOI: 10.1146/annurev.micro.53.1.71
- July 22, 2012
- 07:42 AM
- 271 views
Picocyanobacteria
by Marc in Teaching Biology
This is a guest post by Sophie, written in response to a reader request I am unqualified to fulfil. Picocyanobateria are cyanobacteria that are less than 3 µm in diameter. Their tiny size makes them significant parts of nutrient cycles: their surface area:volume ratios make them very efficient at nutrient uptake, much more so than [...]... Read more »
P. SÁNCHEZ-BARACALDO, P. K. HAYES, & C. E. BLANK. (2005) Morphological and habitat evolution in the Cyanobacteria using a compartmentalization approach. Geobiology. DOI: 10.1111/j.1472-4669.2005.00050.x
Dufresne A, Ostrowski M, Scanlan DJ, Garczarek L, Mazard S, Palenik BP, Paulsen IT, de Marsac NT, Wincker P, Dossat C.... (2008) Unraveling the genomic mosaic of a ubiquitous genus of marine cyanobacteria. Genome biology, 9(5). PMID: 18507822
- July 13, 2012
- 06:19 AM
- 337 views
Tongue Biters and Deep Sea Giants: The Cymothoida (Crustacea: Isopoda)
by Marc in Teaching Biology
The above picture shows a member of the Cymothoida suborder of isopod (Wägele, 1989), containing over 2700 species according to the Smithsonian’s world list of isopods. Cymothoidae (the family, not the suborder; notice the endings!) are well-known across the internet for their wacky parasitic lifestyle (some call it gruesome). The one pictured at the top [...]... Read more »
Lucy Bunkley-Williams, & Ernest H. Williams, Jr. (1998) Isopods Associated with Fishes: A Synopsis and Corrections. The Journal of Parasitology. DOI: 10.2307/3284615
- June 16, 2012
- 10:31 AM
- 359 views
Elysia and Other Photosynthetic Sea Slugs
by Marc in Teaching Biology
Elysia is an “opisthobranch” sea slug famous on the internet for its remarkable ability to photosynthesise, giving it the nickname of “solar-powered sea slug”. It does this by kleptoplasty – stealing plastids from its algal food. If you note the greenish colour in E. asbecki above (Wägele et al., 2010), the green comes from the [...]... Read more »
Mary E. Rumpho, Elizabeth J. Summer, & James R. Manhart. (2000) Solar-Powered Sea Slugs. Mollusc/Algal Chloroplast Symbiosis. Plant Physiology. DOI: 10.1104/pp.123.1.29
Mary E. Rumpho, Farahad P. Dastoor, James R. Manhart, & Jungho Lee. (2006) The Kleptoplast. Advances in Photosynthesis and Respiration. DOI: 10.1007/978-1-4020-4061-0_23
- June 11, 2012
- 08:30 AM
- 353 views
The Exceptional Silurian Herefordshire Fossil Locality
by Marc in Teaching Biology
I’ve often remarked about the amazingness of sites of exceptional preservation (heck, I’ve even done work on the arthropods from one). I’ve already introduced an example. This is another one: the 425 Ma Silurian Herefordshire locality in the UK. The Herefordshire locality preserves animals from a Silurian marine shelf-slope environment, entombed in volcanic ash. The [...]... Read more »
ORR, P., BRIGGS, D., SIVETER, D., & SIVETER, D. (2000) Three-dimensional preservation of a non-biomineralized arthropod in concretions in Silurian volcaniclastic rocks from Herefordshire, England. Journal of the Geological Society, 157(1), 173-186. DOI: 10.1144/jgs.157.1.173
- March 28, 2012
- 07:47 AM
- 351 views
Modes of Speciation
by Marc in Teaching Biology
The most common definition for a species we use is the biological species concept: a population that is reproductively isolated from another population is a different species. Reproductive isolation can be prezygotic, i.e. from before copulation. For example, grasshoppers with different mating calls will not attract each other and mating will not take place. Alternatively, [...]... Read more »
Bolnick, D., & Fitzpatrick, B. (2007) Sympatric Speciation: Models and Empirical Evidence. Annual Review of Ecology, Evolution, and Systematics, 38(1), 459-487. DOI: 10.1146/annurev.ecolsys.38.091206.095804
Wiley, E., & Mayden, R. (1985) Species and Speciation in Phylogenetic Systematics, with Examples from the North American Fish Fauna. Annals of the Missouri Botanical Garden, 72(4), 596. DOI: 10.2307/2399217
- March 24, 2012
- 04:10 AM
- 511 views
Gigantism in Insects
by Marc in Teaching Biology
There are several ecological and evolutionary patterns concerning body size. One of the most observeable ones, consistent among everything from bacteria to plants and animals is the temperature-size rule: species in colder environments tend to be larger, as are members of a population of the same species living in cold environments (Ashton, 2004); the latter [...]... Read more »
Harrison, J., Kaiser, A., & VandenBrooks, J. (2010) Atmospheric oxygen level and the evolution of insect body size. Proceedings of the Royal Society B: Biological Sciences, 277(1690), 1937-1946. DOI: 10.1098/rspb.2010.0001
Kaiser, A., Klok, C., Socha, J., Lee, W., Quinlan, M., & Harrison, J. (2007) Increase in tracheal investment with beetle size supports hypothesis of oxygen limitation on insect gigantism. Proceedings of the National Academy of Sciences, 104(32), 13198-13203. DOI: 10.1073/pnas.0611544104
Shear, W., & Kukalová-Peck, J. (1990) The ecology of Paleozoic terrestrial arthropods: the fossil evidence. Canadian Journal of Zoology, 68(9), 1807-1834. DOI: 10.1139/z90-262
- February 23, 2012
- 11:48 AM
- 421 views
Belidae (Coleoptera: Curculionoidae)
by Marc in Teaching Biology
The Belidae Schoenherr 1826 is one of the eight families of weevil, and contains some of the beetles that obligately pollinate zamiacean and stangeriacean cycads (Crowson, 1991), hence their common name, cycad weevils (I’ve also seen them referred to as “primitive weevils”, a rather inaccurate name). There are ~375 species in 38 genera (Slipinsky, Leschen [...]... Read more »
Norstog, K., Stevenson, D., & Niklas, K. (1986) The Role of Beetles in the Pollination of Zamia furfuracea L. fil. (Zamiaceae). Biotropica, 18(4), 300. DOI: 10.2307/2388573
Soriano, C. (2009) First record of the family Belidae (Insecta, Coleoptera) in amber. New genus and species from the uppermost Albian amber of France. Geodiversitas, 31(1), 99-104. DOI: 10.5252/g2009n1a8
- January 23, 2012
- 04:53 PM
- 524 views
Checkered Beetles (Coleoptera: Cleridae)
by Marc in Teaching Biology
The Cleridae Latreille 1802, known commonly as ham beetles or checkered beetles, are a family of brightly-coloured and hairy predatory beetles, measuring between 3 and 12 mm. They’re easily recognisable by having a narrow pronotum (“neck”), with both the head and the wing bases being wider than it. Clerid larvae are recognisable by having strongly [...]... Read more »
Letourneau, D. (1990) Code of Ant-Plant Mutualism Broken by Parasite. Science, 248(4952), 215-217. DOI: 10.1126/science.248.4952.215
Hansen, K. (1983) Reception of bark beetle pheromone in the predaceous clerid beetle,Thanasimus formicarius (Coleoptera: Cleridae). Journal of Comparative Physiology ? A, 150(3), 371-378. DOI: 10.1007/BF00605026
- January 6, 2012
- 08:27 AM
- 587 views
Fireflies (Coleoptera: Lampyridae)
by Marc in Teaching Biology
The Lampyridae Raffinesque 1815 are the beetles commonly known as fireflies and lightning bugs. There are over 2000 species in over 100 genera, with this being a quarter of the expected diversity (Viviani, 2001). They’re found all over the world and in all sorts of habitats, including aquatic ones (Fu et al., 2005). Their classification [...]... Read more »
Branham, M., & Wenzel, J. (2003) The origin of photic behavior and the evolution of sexual communication in fireflies (Coleoptera: Lampyridae). Cladistics, 19(1), 1-22. DOI: 10.1111/j.1096-0031.2003.tb00404.x
Lewis, S., & Cratsley, C. (2008) Flash Signal Evolution, Mate Choice, and Predation in Fireflies. Annual Review of Entomology, 53(1), 293-321. DOI: 10.1146/annurev.ento.53.103106.093346
Lloyd, J. (1965) Aggressive Mimicry in Photuris: Firefly Femmes Fatales. Science, 149(3684), 653-654. DOI: 10.1126/science.149.3684.653
- November 19, 2011
- 01:08 PM
- 628 views
Culicoidea (Insecta: Diptera)
by Marc in Teaching Biology
The Culicoidea is a superfamily of nematoceran flies (see crudely-modified phylogeny above, from Grimaldi & Engel, 2005). It includes one the most well-known group of organisms, the mosquitoes (Culicidae), as well as three other families: the Dixidae, the Corethrellidae and Chaoboridae. Their sister group is the Chironomidea (containing the Chironomidae, Ceratopogonidae, Simuliidae and Thaumaleidae), all [...]... Read more »
Saether, O. (2000) Phylogeny of Culicomorpha (Diptera). Systematic Entomology, 25(2), 223-234. DOI: 10.1046/j.1365-3113.2000.00101.x
- October 17, 2011
- 09:34 AM
- 708 views
Taxonomic Bias in the Fossil Record: Is it really an issue?
by Marc in Teaching Biology
As a palaeontologist, especially one who doesn’t work on vertebrates and shelled invertebrates, the adequacy of the fossil record for phylogenetics and for finding out evolutionary origins of taxa is a topic I often wrestle with – Darwin himself also famously complained about this issue, devoting an entire chapter to it; all of his complaints [...]... Read more »
Benton, M., Wills, M., & Hitchin, R. (2000) Quality of the fossil record through time. Nature, 403(6769), 534-537. DOI: 10.1038/35000558
- October 6, 2011
- 12:42 PM
- 653 views
Myxozoa
by Marc in Teaching Biology
The Myxozoa count as some of the most enigmatic organisms known. There’s around 1350 species of them, all tissue and cellular parasites. The majority infect aquatic and marine fish, while some use platyhelminths, annelids, reptiles, amphibians (e.g. Hartigan et al., 2011) or moles as primary hosts. One freshwater bryozoan parasite whose affinity has been debated [...]... Read more »
Evans, N., Holder, M., Barbeitos, M., Okamura, B., & Cartwright, P. (2010) The Phylogenetic Position of Myxozoa: Exploring Conflicting Signals in Phylogenomic and Ribosomal Data Sets. Molecular Biology and Evolution, 27(12), 2733-2746. DOI: 10.1093/molbev/msq159
- October 3, 2011
- 08:27 AM
- 624 views
Freaky Parasites: Chelonus
by Marc in Teaching Biology
I’ve already written a post about parasites that affect their hosts’ behaviour, but it’s such a cool subject that I don’t think anyone will mind another example of it :) Species in the braconid genus Chelonus are egg-larval parasitoids. Parasitoids are parasitic in their larval stage and free-living as adults. Egg-larval parasitoids are those that, [...]... Read more »
KAESLIN, M., PFISTERWILHELM, R., & LANZREIN, B. (2005) Influence of the parasitoid and its polydnavirus on host nutritional physiology and implications for parasitoid development. Journal of Insect Physiology, 51(12), 1330-1339. DOI: 10.1016/j.jinsphys.2005.08.003
- September 25, 2011
- 04:26 AM
- 620 views
Barnacles (Crustacea: Cirripedia)
by Marc in Teaching Biology
Cirripedes (barnacles) are known for their sessility – it’s their defining characteristic. They count as one of the first model organisms of evolutionary biology, having been comparatively studied by Darwin for over 8 years (they were probably his favourite animals). The 4 resulting monographs (two for Recent, two for fossil) are still some of the [...]... Read more »
Høeg, J. (1995) The biology and life cycle of the Rhizocephala (Cirripedia). Journal of the Marine Biological Association of the United Kingdom, 75(03), 517. DOI: 10.1017/S0025315400038996
- September 19, 2011
- 12:32 PM
- 682 views
Onthophagus Horn Dimorphism
by Marc in Teaching Biology
One of my side-projects at the moment is setting up a project to observe the behaviour and life history of male Onthophagus dung beetles (Scarabaeidae). This post will introduce why this is of interest (to me, at least). First, a bit about the study species. As far as is currently known, there is only one [...]... Read more »
Gotoh, H., Cornette, R., Koshikawa, S., Okada, Y., Lavine, L., Emlen, D., & Miura, T. (2011) Juvenile Hormone Regulates Extreme Mandible Growth in Male Stag Beetles. PLoS ONE, 6(6). DOI: 10.1371/journal.pone.0021139
Emlen, D., Corley Lavine, L., & Ewen-Campen, B. (2007) Colloquium Papers: On the origin and evolutionary diversification of beetle horns. Proceedings of the National Academy of Sciences, 104(suppl_1), 8661-8668. DOI: 10.1073/pnas.0701209104
- September 8, 2011
- 04:22 PM
- 1,014 views
Chengjiang
by Marc in Teaching Biology
One of the highlighted Konservat-Lagerstätten in my Rise of Animals post is Chengjiang (a.k.a. the Maotianshan Shales). While Burgess has the historical significance, in terms of importance and potential, Chengjiang is arguably more important (see Shu, 2008). Chengjiang fossils are not the easiest to see, although they are admittedly abundant, at 40000+ specimens so far. [...]... Read more »
Zhu, M., Babcock, L., & Steiner, M. (2005) Fossilization modes in the Chengjiang Lagerstätte (Cambrian of China): testing the roles of organic preservation and diagenetic alteration in exceptional preservation. Palaeogeography, Palaeoclimatology, Palaeoecology, 220(1-2), 31-46. DOI: 10.1016/j.palaeo.2003.03.001
Steiner, M., Zhu, M., Zhao, Y., & Erdtmann, B. (2005) Lower Cambrian Burgess Shale-type fossil associations of South China. Palaeogeography, Palaeoclimatology, Palaeoecology, 220(1-2), 129-152. DOI: 10.1016/j.palaeo.2003.06.001
- August 20, 2011
- 05:55 AM
- 982 views
Stomatopod Rumblings
by Marc in Teaching Biology
I thought I had covered the basics of every aspect of stomatopod biology in my stomatopod post, as did all the readers (thanks again for the wonderful feedback!). But I missed one part: acoustics and its role in communication and ecology. It’s obvious that the raptorial appendage will make a loud pop when it strikes, [...]... Read more »
Staaterman, E., Clark, C., Gallagher, A., deVries, M., Claverie, T., & Patek, S. (2011) Rumbling in the benthos: acoustic ecology of the California mantis shrimp Hemisquilla californiensis. Aquatic Biology, 13(2), 97-105. DOI: 10.3354/ab00361
- August 19, 2011
- 06:59 AM
- 1,070 views
The Importance of Taxon Sampling: An Example from the Snout Butterflies (Lepidoptera: Libytheinae)
by Marc in Teaching Biology
Continuing from yesterday’s theme of injecting some personal remarks (and to make it 3 posts in a row on butterflies, for no particular reason), I want to note something about this Wahlberg et al. (2005) tree (opens in a new window/tab!) that I reprinted in each of the posts, specifically to point out a supposedly [...]... Read more »
Wahlberg, N., Braby, M., Brower, A., de Jong, R., Lee, M., Nylin, S., Pierce, N., Sperling, F., Vila, R., Warren, A.... (2005) Synergistic effects of combining morphological and molecular data in resolving the phylogeny of butterflies and skippers. Proceedings of the Royal Society B: Biological Sciences, 272(1572), 1577-1586. DOI: 10.1098/rspb.2005.3124
topics
join us!
Do you write about peer-reviewed research in your blog? Use ResearchBlogging.org to make it easy for your readers — and others from around the world — to find your serious posts about academic research.
If you don't have a blog, you can still use our site to learn about fascinating developments in cutting-edge research from around the world.
