Most people are familiar with Darwin's finches as an example of divergent evolution and how this influenced Darwin. The story behind the finches is this: Darwin went to the Galapagos and he collected some birds. The finches were so different he thought they were from different families (e.g., wrens, finches, and orioles). Back in England, Darwin runs into ornithologist and illustrator extraordinaire (and creationist) John Gould. Gould tells Darwin that the finches are actually all related. Darwin is like "wth Gould." Some of the details are left off the labels so he can't tie specific location (island) to a specimen. Mind you, Darwin is a novice and recent graduate and in his early 20's so he should get some slack. It's actually the mockingbirds and tortoises that get Darwin thinking. Why should each island have its own species of mockingbird and tortoise? The rest is evolution and natural selection. The finches come later when thinking about why there is divergence and the different beaks allow different species to exploit different resources. On Galapagos our local guides didn't know the different species of finches. I don't blame them - they all look very very similar and they're not trained to ID them. Our guides were very good organizers and knew tons, just not the finches. Here are some of my best pictures of these little buggers.
"I have not as yet noticed by far the most remarkable feature in the natural history of this archipelago; it is, that the different islands to a considerable extent are inhabited by a different set of beings. My attention was first called to this fact by the Vice-Governor, Mr. Lawson, declaring that the tortoises differed from the different islands, and that he could with certainty tell from which island any one was brought. I did not for some time pay sufficient attention to this statement, and I had already partially mingled together the collections from two of the islands. I never dreamed that islands, about 50 or 60 miles apart, and most of them in sight of each other, formed precisely the same rocks, placed under a quite similar climate, rising to a nearly equal height, would have been differently tenanted; but we shall soon see that this is the case." Charles Darwin, Voyage of the Beagle
Each of the largest islands has a set of organisms that are largely not found on the other islands. The first example presented is that the governor could identify the origin of a tortoise from the shape of the shell. But there are more as Darwin hints and I'll let him tell the rest.
"The day was overpoweringly hot, and the lake looked clear and blue: I hurried down the cindery slope, and, choked with dust, eagerly tasted the water-but, to my sorry, I found it salt as brine.
The rocks on the coast abounded with great black lizards, between three and four feet long; and on the hills, an ugly yellowish-brown species was equally common. We see many of this latter kind, some clumsily running out of the way, and others shuffling into their burrows." Charles Darwin, Voyage of the Beagle
The first is the marine iguana, which I think nearly everyone familiar with the story of Darwin and the Galapagos knows. I had no idea what the second is so I looked it up. Darwin's description is too vague to determine the particular species but he's probably referring to one of the over-twenty species of lava lizards that occur on the Galapagos Islands. Now I know!
23 Jan 2014: "Generally the atmosphere is hazy; and this is caused by the falling of impalpably fine dust" -Charles Darwin, Voyage of the Beagle
Still off the west coast of Africa, Darwin is remarking on the clouds of dust coming from Africa. These clouds are laden with enough dust to bother the eyes and damage equipment. Darwin collected a number of samples and sent them off to be analyzed. The results intrigued Darwin; the dust was primarily composed of the remains of freshwater organisms and plants and to a lesser extent marine organisms.
Darwin's dust samples were taken hundreds of miles away from the African continent. Data suggests that the amount of dust varies by year and decade and can influence climate over the Atlantic (Evan et al. 2011). The amount of dust, in turn, is determined by land use and climate over Africa.
7 Jan 2014: "saw two very bad operations, one on a child, but rushed away before they were complete" Darwin autobiography
Darwin enrolled as a medical student at Edinburgh University. Bored by his anatomy professor and disgusted by dissection, it was not looking good for his career as a doctor. Moreover, he was figuring out that his inheritance would allow him to live comfortably without working so there was little incentive to push himself at his studies. One could not be idle but there was no rush.
After watching, almost watching, an operation on a child, Darwin never returns to the surgery room. At the time patients were held down and cut open "before the blessed days of chloroform."
Hot water pipe is frozen. Blow driers going like mad on the basement pipes. Coffee maker works and the internet is functional. We're good.
Sunday, January 5, 2014
MY YEAR OF DARWIN (#YEAROFDARWIN)
5 Jan 2014: ""In my simplicity I remember wondering why every gentleman did not become an ornithologist" Darwin autobiography
At 44 years old, I still wonder the same thing. Darwin was reading natural history books during his childhood and his interests were broadening to include insects, minerals, and birds. Darwin was spending time in the beautiful countryside of Wales. Being outside inspires - do it. I also spent my days wondering the woods near my home and the Pohatcong Creek was my playground. I do many programs with local schools and none of the schools take students out in the field - ever. I don't have any data on hand but I suspect there are fewer children headed into the woods both in absolute numbers and proportionally across the population. The result might be an increasing intellectual and emotional disconnect between us and nature (recently coined Nature Deficit Disorder). So hopefully, catching birds with WEBS (Women Empowered By Science) can address some of that in my little bubble.
Just over 0 today and the bird feeders are draining quickly. Had a male Cooper's Hawk swing by the house and miss getting one of the 50-some House Sparrows. Working on a National Science Foundation proposal today.
