I’m really enjoying running on-line tuts with Schol Bio students, because the questions & discussions are so interesting. (So, hopefully the students enjoy them too!) Last week we got onto talking about the enzyme lactase and the fact that in some populations many individuals continue to produce it into adulthood (thus making them lactose-tolerant, & […]
Continue readingCategory: evolution
mastodons in greenland
What is a mastodon, anyway? Like mammoths (on the left in the image above), mastodons were common during the last ice age, but the two elephant-like creatures are fairly distant relatives. The more-familiar mammoths were close cousins of modern elephants (a fact that is of interest to those considering doing a Jurassic Park on mammoths – […]
Continue readingcrabs, carcinization, and crappy headlines
This is a post of two parts: the interesting tale of convergence involving crab-like creatures, and the very poor – nay, crappy (because I like the alliteration) – headline on a popular article about it. Part 1: the history of carcinization in crustaceans, described in this 2017 paper in the Biological Journal of the Linnean Society […]
Continue readingis it a shrimp? is it a prawn? no – it’s Super Crayfish! (revisited)
I wrote this post a couple of years ago, but I think it’s worth revisiting it. Why? Because these crayfish are in the news again – apparently they’ve “taken over” a Belgian cemetery (or, more correctly, the waterways in that cemetery). Local scientists believe that someone must have had the crustaceans in a home aquarium […]
Continue readingfirst steps: jerry desilva on the evolution of bipedalism
This morning I got up (at the rather early and unaccustomed hour of 3.30am) to listen to a webinar by paleoanthropologist Dr Jeremy DeSilva¹. Titled “First Steps”, his presentation was about the origins of bipedalism in the human lineage. It was a fascinating session & I thought I’d turn my notes into this post, to […]
Continue readingthe past, present, & future of orca in north america’s pacific northwest
n July this year, the Seattle Times ran a story on an orca called Tahlequah – she was pregnant, again. And just yesterday, she gave birth. The story is particularly noteworthy because a couple of years ago, Tahlequah also bore a calf, which died, and she then carried the dead baby on her nose for […]
Continue readinga fishy story: midas cichlids in nicaraguan lakes
Midas cichlids (Amphilophus spp.) are a popular aquarium fish, but in the wild they’re found in South America, ranging from Nicaragua to Costa Rica. The 2018 Schol Bio paper included a really interesting question about a Nicaraguan ‘species complex‘ of these fish, based on a paper in Nature Communications. and a monograph in Cuadernos de […]
Continue readinghoneycreepers in hawaii
The 2015 Schol Bio paper included a question about a group of birds known as honeycreepers, specifically, the 56 species endemic to the Hawaiian islands. (Or, were endemic: 18, or perhaps 19, are still living; the others are extinct.) Students who’ve already had a look at this paper as part of their preparation for the exam will […]
Continue readingneandertals’ genetic legacy extends into africa
For the last few years it’s been pretty much received wisdom that African populations shared only a tiny proportion of their genes, if any, with Neanderthals. In contrast, other non-African sapiens populations had a small but significant admixture of Neanderthal genes. The underlying reason for this, it’s been assumed, is that Homo sapiens and neandertalensis only bred with […]
Continue readingzombie ants, updated
Image source: David P. Hughes, Maj-Britt Pontoppidan – http://www.plosone.org/article/showImageLarge.action?uri=info:doi/10.1371/journal.pone.0004835.g001 CC BY 2.5, https://commons.wikimedia.org/w/index.php?curid=17917778 Back in 2010 I wrote about the strange tale of the zombie ants, which do the bidding of their fungal overlords. (They’re not an isolated example; a range of parasites change their hosts’ behaviour. See here and here for example – though as you’ll find, […]
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