Tuesday, July 31, 2007

Address the mess

Something a little lighter for the final ecology post, courtesy of Comedy Central. They invite you to address the mess and find out just how environmentally unconscious you are.

But if I may introduce a slightly serious point, the problem with quizzes like this one (and yes I do know this one isn't meant to be serious), and even the earth footprint calculator, is that they tend to lump all environmental behavior together. This can lead people to think that by recycling, carrying their own coffee mug around and switching off lights they are helping save the planet. I suppose every little helps but it takes an awful lot of little things to make up for some of the big ones and quizzes and surveys like this could do a much better job if they pointed out the impact of each behavior. The earth footprint calculator almost does this on the final page but I don't know why they don't have the 'impact' of each answer pop up as you answer it. It's not as if people are going to cheat on the quiz (are they?) Then it would be clearer that it's nice to recycle but no amount of recycling will make up for even just a few plane trips.

This time last year: Bug Soup and Pathogens determined to attack inside the United States.


Monday, July 30, 2007

Disease snippets

Just from today:

A cruise liner hit by a suspected outbreak of legionnaires' disease is due to return to Britain today. (July 30)

Russia dealing with Legionnaire's outbreak. (July 30)

Doctors Debate Over Lyme Disease: Patients ache as doctors disagree about whether there is a chronic form of the tick-borne malady. (July 30)

Personal Health Beliefs Are Largely Hit and Myth. False or Outdated Sense Of Risks Is Widespread, Cancer Study Shows. (July 30)

Global Warming Could Harm Health. Evidence Indicates Climate Change Could Affect Individuals, In Addition To Planet As Whole. (July 30)

In addition The Ecological Society of America have a short factsheet on Hanta Virus, to illustrate that even ecological research with no apparent direct applications can sometimes turn out to be of vital importance.

This time last year: The lost Children of Rockdale County and Mad Cow.

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Sunday, July 29, 2007

Ecosystem services: a primer

The Ecological Society of America (ESA) provides a nice summary of the idea of ecosystem services at their website: Ecosystem Services: A Primer
Take a look at the article and then at the end you can follow up some of the links. For example there is an interesting interview with Gretchen Daly, one of the authors of an article that attempted to put a dollar value on ecosystem services ($33 trillion if you are curious).

This time last year: Shipbreaking. Not to be confused with Shipbuilding, the Elvis Costello song, that is about the Falklands war, although no-one here seems to know that.

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Friday, July 27, 2007

Bee services

On Thursday I introduced the idea of species as providers of ecosystem services. An example of an ecosystem service is the pollination of our crops that is carried out by insects. The KQED science program Quest recently featured UC Berkeley ecologist Claire Kremen, and her research on bee pollination. In addition, an online-only special features the urban bees of Berkeley entomologist Gordon Frankie.

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Thursday, July 26, 2007

More snippets

Vital ecosystem functions, such as sequestering carbon dioxide and purifying water, depend on a larger number of species than previously thought. From a Nature article this month. Read the article here and a news summary here.

The rainforest fragmentation experiment I described in lecture, the one with 1, 10 and 100 hectare plots, is now in danger of destruction itself. The experiment has been going on since 1979 and has produced an invaluable long term data set. The nearby town of Manaus has grown rapidly since being declared a free-trade zone in the 1970s, with a population of 1.7 million people. Settlers are now moving onto the land around the project and raided a research camp last year. A fire lit by the new arrivals also destroyed several study plots. News report from this week and the experiment's web site.

More species than we thought? It turns out we may not even know how many species there are in the places we thought we did know well. Cryptic species – animals that appear identical but are genetically quite distinct – may be much more widespread than previously thought a paper published this week alleges. The findings could have major implications in areas ranging from biodiversity estimates and wildlife management, to our understanding of infectious diseases and evolution. Read the Research paper published last week here. This also means that what I told you about us knowing how many large species there are may also be up for debate. In 2001 a new species of African elephant was discovered, not by looking under bushes, but by genetic analysis of existing African elephants which suggested two groups distinct enough to warrant species status: The African Bush Elephant and the African Elephant. (Research report on the new elephant species).

People consume a massive 24% of Earth's production capacity, depleting species and habitats - and things could get worse if more land is used for biofuel crops. By comparing carbon consumption through human activity with the amount of carbon consumed overall researchers found that humans use 15.6 trillion kilograms of carbon annually. Read the PNAS paper published this month here.

This time last year: Save the Rhino Maggot!, Specicide, Bird Extinction Rates and Snakes on a Plane.

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Wednesday, July 25, 2007

Found today, gone tomorrow

Hummingbirds are amazing. I must confess that when I first came to California I had no idea that you had hummingbirds here. I can still stare at them in wonderment. They're just so small, and feisty.

A new species of hummingbird, the gorgeted puffleg, has been discovered in the mountains of Colombia, but environmentalists fear the discovery will be short-lived – the bird is already threatened with extinction.

The bird was first spotted in 2005 and new expeditions in 2006 confirmed it as a new species of hummingbird - Eriocnemis isabellae.

Unfortunately it is thought that the bird's range must be very small in order for it to go undiscovered for so long and the bird's habitat is being threatened by slash-and-burn agriculture and encroaching coca fields.

There is a report on the discovery in New Scientist here.

The picture is pretty cool. Something about it reminds me of the infamous youtube praire dog 'dramatic look' video.

This time last year: Rachel Carson, Fred Soper and DDT


Tuesday, July 24, 2007

Fish Farming

Perfectly timed for our mutualism lecture is this report from yesterday that the dusky damselfish has joined a select group of species, including humans, ants, and salt-marsh snails, that are known to cultivate beneficial crops. The fish rely on the algae as a source of food, but the algae also benefit because they only survive well if they are farmed. The algae farms are kept both protected and weeded by the damselfish. Unwanted sea urchins and starfish are ejected from the farms, and unpalatable algae are meticulously weeded out to promote lush turfs of the preferred species. When the damselfish are removed from the 'farms' it only takes a couple of days for other grazing fish to move in and obliterate all the algae growing inside the gardens.

This time last year: Mt. St. Helens and Wiki1B again

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Monday, July 23, 2007

Encyclopedia of the Environment

If you have read this blog much you'll know I'm a big fan of Wikipedia. One of the reasons I like it is that it has, largely, emerged organically from the passion of dedicated enthusiasts. It is not being driven by a huge corporation. However as criticisms of Wikipedia grow it isn't clear what will triumph in the long run. Will Wikipedia emerge as a giant in the Google mold, or will it be replaced by more specialized encyclopedias? Numerous contenders are already emerging from the amusing Conservapedia (which always reminds me of Stephen Colbert's quote at the White House Correspondent's Dinner that 'reality has a well known liberal bias') to the more specialized 'Encyclopedia of the Environment' which addresses the issue that Wikipedia is not peer reviewed by having all their articles peer reviewed. Lots of interesting stuff there from classic ecological and environmental papers such as Garret Hardin's Tragedy of the Common's paper to great speeches by Jimmy Carter and Mother Jones, and lots of articles on ecological topics.

Whilst we are on the subject don't forget to check out our very own Wiki1B.

This time last year (another of my favorite posts): Honey Guides, Killer Bees and Land Mines.


Sunday, July 22, 2007

Rise of dinosaurs not so rapid after all.

I didn't want to let this press release from researchers in Integrative Biology at UC Berkeley slip by. They showed, for the first time, that dinosaurs and their non-dinosaur ancestors lived side by side for tens of millions of years, disproving the notion that dinosaurs rapidly replaced their supposedly outmoded predecessors.

The finds, including fossil bones of a new dinosaur predecessor the researchers have named Dromomeron romeri, are described in a cover story in the July 20 issue of Science.

This time last year: 100 Ecological Questions and Global Warming threatens California Wine Industry

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Friday, July 20, 2007

Evolution is easy!

Thanks to the wonderful folks at BoingBoing (a directory of wonderful things) for directing my attention to this fabulous cultural artifact: a Red Queen Barbie doll! Part of a new line of Alice in Wonderland Barbie toys. Buy this one and all your other Barbie dolls will have to run twice as fast just to keep up.

The only disappointment is how, well, static, the Red Queen looks. Perhaps she should come with a catapult launcher.....

Although Barbie is well known for his difficulty with math she has already revealed a fondness for evolution: witness the Paleontologist Barbie. I love the 'Dinosaur Quiz' on the back - 'if you get five or more right you should consider a career in paleontology too!' Sadly the text is too small to read the actual questions. Although I think one of them may be 'What does Dinosaur mean?' Fortunately diligent searching of the ebay archives produces this better image. Now you too can take the quiz and even check the answers to find out if you too can be a paleontologist!

This time last year: Ecological Footprints and Summer Reading part 2

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Thursday, July 19, 2007


The issues we discussed at the end of today, human population growth and overconsumption, are also neatly summarized in the idea of an 'ecological footprint.' I think this idea is discussed in Campbell but there are several websites that develop this idea. First proposed in 1992 by William Rees, a Canadian ecologist, ecological footprint analysis approximates the human impact upon the environment by calculating the ecologically productive land and marine area required to sustain a population, manufacture a product, or undertake various activities.

I like this Global Footprint Network Site because it lets you see, and calculate if appropriate, world, national and individual footprints. There's lots of interesting stuff here. Check out the World Consumption Cartogram. It's interesting to view this on a national level because some countries and areas will have large footprints because of their large populations and others will have large footprints because of their large consumption.

This time last year: How many people can the earth support?


Wednesday, July 18, 2007

Worth a thousand words

If you like your news with cool photographs you should bookmark National Geographic's 'Photos in the News' page.

Here are some recent stories relevant to this class:

New 'Wasp' Orchids tempt male bugs. In a crafty evolutionary hoax, six newly discovered orchid species are shaped like female wasps to trick males into pollinating them.

Baby Mammoth found frozen in Russia. A six-month-old baby mammoth found in Russia's remote Siberian north is the best preserved example of the species ever recovered.

It's those giant penguins again. Two species of ancient penguin have been uncovered in a Peruvian desert, including one that stood almost 5 feet (1.5 meters) tall, a new study reports.

Surprising herds discovered in Southern Sudan. Aerial pictures reveal vast herds of antelope, elephants, and ostriches flourishing in Southern Sudan, despite decades of war.

Amazon expedition discovers dozens of new animals. A flashy purple frog and a kissy-faced catfish are among the 24 new animal species recently discovered by scientists working in the remote highlands of Suriname.

This time last year: Leonard Cohen's March of the Penguin's and Elephants in Space

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Tuesday, July 17, 2007

Rat Reciprocity

What is it that makes us uniquely human? Is it our intelligence, no, dolphins and monkeys are plenty smart. Is it our capacity for self-awareness? Nope, apes, dolphins and elephants have been shown to be self-aware. Mourning the dead? Nope, elephants do that. In fact we could go through a pretty long list of traits that we might think are uniquely human, only to find one or more animal species that also show this trait. So its a relief to find a study published this week that allows us to hold on to the one trait that, so far at least, remains uniquely human - spite. (Incidentally there are very few scientific experiments I'd want to watch on video but I'd make an exception for this one. Chimps and collapsing tables of food sound like a great combination).

Also, just published, the first evidence of an unusual form of altruism, termed 'generalized reciprocity': Generalized Reciprocity in Rats. In the first example of general cooperation in any animal, rodents helped by unfamiliar rats are found to help strangers themselves.

This time last year: Running after Antelope


Monday, July 16, 2007

Understand the rules before you break them.....

In a different class I give a lecture on how to give an oral presentation. After going through a pretty big list of do's and don'ts I finish by pointing out that all good speakers will break one or more rules. In my mind though it is still important to understand the rules, not so you can slavishly follow them, but so you know when you are going against convention. Bottom line - always understand the rules before you break them. I think that is generally a good motto for life too.

That is why I go, as clearly as I can, through the scientific method, despite the fact that some fairly influential thinkers have argued that most scientists don't even operate in this way. Again, I would argue that it is vital to understand the rules so that you can see the consequences of breaking them. A noted Berkeley connection is the philosopher Paul Feyerabend who spent three decades associated with UC Berkeley. Feyerabend was critical of not just the idea of the scientific method but was also critical of the idea of the philosophy of science itself - a critical guy. You can read accessible and interesting introductions to his work at both Wikipedia and at the Stanford Encyclopedia of Philosophy. (My definition of 'accessible' is that you can read the article and understand what most of the words mean and the gist of what they are saying. My definition of 'interesting' is that it made me go hmmm.)

If you look at any article in a scientific journal you will also notice that it isn't neatly laid out like the slide I showed with 'Data', 'Hypothesis', 'Prediction' etc. Although these words will be tantalizingly scattered throughout the text. In a bid to demystify the somewhat arcane style of scientific writing, the journal Science has selected a number of scientific articles from that journal and annotated them, illustrating how different parts of each article embody the scientific method. This is part of the 'Keystones of Science project'. Here is an annotated example of the scientific method example titled Microbial Genes in the Human Genome: Lateral Transfer or Gene Loss?.

This time last year: Dr Dino versus the Amazing Randi


Sunday, July 15, 2007

Evolution Blogs

For the last evolution post I'd like to recommend a couple of evolution related blogs you may enjoy if you wish to explore some of the topics we touched on, and many we didn't, further.

PZ Meyers Pharyngula blog is self-described as 'Evolution, development and random biological ejaculations from a godless liberal'. That seems to describe it fairly well. PZ Myers is a biologist and associate professor at the University of Minnesota (and the pharyngula period is a stage in the embryonic development of vertebrates).

Speaking of the godless, and I mean that quite genuinely, Richard Dawkins has two websites/blogs that are well worth checking out. The official Richard Dawkins website self-described as 'A Clear-Thinking Oasis' and the Richard Dawkins Foundation for Reason and Science (another Clear-Thinking Oasis'). Richard Dawkins holds the Charles Simonyi Chair for the Public Understanding of Science at Oxford University. He came to prominence through his 'Selfish Gene' book in 1976, a book that all Biology undergraduates at my University were recommended to read a decade after its publication - a recommendation I am happy to pass on thirty years after its publication. Lately Richard Dawkins has been rather prominently involved in the debate between creationism and evolution and is often described, usually by others, as an 'outspoken atheist'. His latest book, 'The God Delusion', combines his work on evolutionary biology and his passionate atheism to ask why, if there is no god, a belief in one so widespread and prominent as to be almost universal? In the hands of an evolutionary biologist this turns out to be quite an interesting question.

Onward to Ecology.....

This time last year: What, if anything is a Preble's Jumping Mouse?


Saturday, July 14, 2007

When Giant Penguins Roamed the Tropics and other Snippets

What a great word: 'Snippets'.

A good way to get entertained and keep up with news in the sciences is to read New Scientist magazine. Although it is British, there really isn't an American equivalent and the magazine has become much more international over the last few years. It really isn't that expensive to subscribe especially since it is a weekly magazine but you can also read many of the articles on their website (or in the library copy of course). Although they do have a few longer articles each week, much of the magazine consists of brief news reports on recent research.

Here are a few of the evolution related articles they have published recently:

Gut parasites came from the deep: A genetic comparison finds links between bacteria from deep-sea vents and those from the human body. 7 July 2007

When giant penguins roamed the tropics: Millions of years ago, human-sized penguins roamed the Peruvian coast just 14 degrees south of the equator, according to new fossil evidence. 25th June 2007
Cooler climes help spur on evolution: Tropical hotspots of biodiversity are not the hottest as far as evolution is concerned. 23 March 2007

Looking for larvae in ancestral genes: Did our earliest animal ancestors go through a larval stage, or did that evolve later? 26 January 2007

and one from last year, illustrating the tendency of New Scientist to try and bridge the gap between more popular journalism and science writing. I'm guessing the original research report did not have this title - Mums help chicks if dad was ugly: Females appear to invest extra energy into getting their poorer-quality offspring off to a good start, at least among house finches. 29 September 2006
(I just checked, the title of the research article is: Yolk Antioxidants Vary with Male Attractiveness and Female Condition in the House Finch (Carpodacus mexicanus))
This time last year: Darwin's Finches

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Friday, July 13, 2007

Midterm 1 Results - 2007

The first midterm has been graded and your GSI's will give you your individual results next time you meet with them. Please don't e-mail me - I don't have the individual results, just the overall summary.

However some of you may be interested in this, especially when you have your own grade.

Overall there were 259 students, the mean was 80% and the median was 84%. This difference is typical for skewed distributions and is why the median is a better descriptor. If you got 84% (the median) then half the class scored more than you and half the class scored less.

Overall 37% of the class scored in the A range (>90%), 25% in the B range (>80%), 18% in the C range and 10% each in the D and F range.

These results are similar to previous years (see link below for last years results) with one small exception - a much higher number of students than usual got a perfect score. This year an impressive 12 students got 100% on this midterm. Well done.

As usual I have looked at the answer distribution for all the questions to check for problems.

Lowest % correct was 57% for Q27 (polydactyly in cats - despite the word DOMINANT being in bold capitals, a significant number of people provided the allele frequency that would have been correct if it was a recessive trait) and 50% for Q 37 (the calculation on the seed discarding plant breeder that was meant to be a fairly difficult question).

Highest % correct was 98% (one question).
I have looked closely at all the questions where either less than two thirds of you got the correct answer (6 questions) or more than 20% of you picked a particular incorrect answer (4 questions) and don't see any problems.

Section means were similar and no section was more than 4% away from the overall mean of 80%.

This time last year: Midterm 1 Results and Web Sight


Thursday, July 12, 2007

Male killer

Currently the lead story on the News section on the UC Berkeley Home page is about a study that shows natural selection in action and illustrates the Red Queen principle.

Wolbachia is a is a genus of inherited bacterium that infects a high proportion of all insects. They are the world's most common parasitic microbes and often lead to the death of males.

Over only 10 generations that spanned less than a year, the proportion of males of the Hypolimnas bolina butterfly on the South Pacific island of Savaii jumped from 1 percent of the population to about 39 percent. The researchers considered this a stunning comeback and credited it to the rise of a suppressor gene that holds in check the Wolbachia bacteria, which is passed down from the mother and selectively kills males before they have a chance to hatch.

"To my knowledge, this is the fastest evolutionary change that has ever been observed. This study shows that when a population experiences very intense selective pressures, such as an extremely skewed sex ratio, evolution can happen very fast."
Sylvain Charlat

The actual paper will come out in the journal Science tomorrow.

The fieldwork for this study was carried out on two South Pacific Islands and the researchers were based out of UC Berkeley's Gump Richard B. Gump South Pacific Research Station on the island of Moorea in French Polynesia. I mention this because this field station is also the home for IB 158/ESPM 107 : Biology and Geomorphology of Tropical Islands - a semester long course that spends 9 weeks at the field station.

This time last year: Woof!

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Wednesday, July 11, 2007

Sex, sex, sex

Science is never so much fun as when it is a little controversial. When you add this to the fact that everybody likes to argue about sex we have a recipe for fun, fun fun.

Just when it looked like the red queen hypothesis was gaining the upper hand as an explanation for the prevalence of sex across the animal and plant kingdoms it has started to struggle to explain why species have so much sex. Why not reproduce asexually most of the time to get the benefits of that strategy and throw in a little sexual reproduction here and there for variety (literally)?

There's a nice essay by Matt Ridley on the PBS Evolution website that discusses the issues we talked about in class.
Here's a BBC report from a paper in 2004 which takes the issue further and asks whether the Red Queen hypothesis can really explain why we have so much sex...
And to bring us up to date here's a link to a report on a paper from 2006 that argues that the Red Queen hypothesis does just fine if we take into account the maternal transmission of parasites.

This time last year: The Demon in the Freezer

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Tuesday, July 10, 2007

Blog fun

I don't want to make people paranoid but you do leave traces in cyberspace.

I have a simple web counter on this site (click on the number at the bottom of the page, or here, to see it). This is just the free version - the paid version would probably give me much more information. Check it out to see what information ANY website can collect on you.

I don't use it much but it's nice to see that people are using this site. It's also often amusing to see the search terms that bring people here. Last year I started a list of some of the best ones (people search on some very weird things) but here's a few that made me chuckle today. (Although, as you may have noticed, I am fairly easily amused....)

latto first midterm - Nice try buddy.
very fat mouse picture - Okay, who else immediately did a google image search on this?
scorpion chasing duck - What? Why?
zedonk sale


First, be careful when you do a google search on 'dominance'. I'm so naive sometimes.....

Anyhow, an interesting question came up today - what IS dominance? What causes one allele to be 'dominant' to another?

In certain cases it is pretty simple. The production of 'something' tends to be dominant to the production of 'nothing'. So 'wild type' alleles tend to be dominant to mutants that code for nothing. If the allele is coding for the production of an enzyme and a single copy of the allele produces more than enough then the heterozygote and the homozygote will have similar phenotypes - complete dominance. However if the homozygote produces just enough then the half expression of the heterozygote may result in a different phenotype. The pink flowers would be a good example here. The pink comes about by the production of only half as much red pigment.

After this it gets a bit more complicated and was, in fact, the subject of a fairly intense debate in the last century between two giants of the population genetics world: RA Fisher and Sewall Wright. If you are interested in this topic then here are a couple of entries into the literature: a blog post entitled ' Whatever happened to the Fisher-Wright controversy?' and an article in the Journal of Theoretical Biology on 'The Heat-shock Response and the Molecular Basis of Genetic Dominance'.

This time last year: Canterbury Tales

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Monday, July 09, 2007

Hox genes

If regulatory genes can be likened to movie directors then the Homeobox genes (or Hox genes for short) are the Martin Scorsese of the gene world. They certainly get a lot of press and they may well be geniuses.

Hox genes encode transcription factors which switch on cascades of other genes, for instance all the ones needed to make a leg. This means that despite being fairly small (only 180 base pairs long in humans) they can have huge effects.

You can read about the discovery of Hox genes at the Howard Hughes Medical Institute and there are several interesting articles about Hox genes at the Pharyngula blog. Here's one on Hox genesis, and there's an overview of Hox genes here.

This time last year: The Thagomizer


Sunday, July 08, 2007

Learn to fish

There is a very widely known saying:
'Give a man a fish and you feed him for a day. Teach a man to fish and you feed him for a lifetime.'
Variously attributed to 'Unknown', 'Chinese Proverb' or 'Lao Tzu'.

This saying is very pertinent to teaching. Sometimes it's a lot easier to hand out fish! However sometimes it's easy to teach a few fishing tricks. Here's one that you can use for the rest of your Berkeley career, and beyond, that surprisingly few people seem to know about. I may mention this in class on Wednesday but you read it here first.

Now that the Internet has calmed down a bit from its initial birth pangs many sites have fairly reliable url's. These include websites for large classes such as Bio1B. For example the Bio1B website has been http://ib.berkeley.edu/courses/bio1b/ since 2001. You can use a site like the Internet archive to go back in time to look at the site in the past. Why would you want to do that? Well you can easily pull up reading lists from the 6th or 5th edition and you can find some past quizzes that might be useful for review. You don't need to restrict yourself to the summer you can look at sample exams that might have been posted by others that teach this course. Of course they may cover some things we don't and vice-versa but there will be a LOT of overlap - we do compare notes and syllabuses you know!

This time last year: Brave New World

Saturday, July 07, 2007

Weird Life

I don't want to claim to be a good at predicting the future (I'm not) but I do want to say that one of the few predictions I have bored people with for some years is now given some tentative support by a very prestigious group.

“Nothing would be more tragic in the American exploration of space than to encounter alien life and fail to recognize it.”

A report just published the National Research Council (NRC) suggests that the search for extraterrestrial life beyond Earth’s solar system should be widened to include investigations that includes “weird” life. The whole report is available online here or you can read their news report.

Next week we will consider the origin of life, and indeed, what we even mean by life

I think this is post #100. Yay.

This time last year: Missing Links, Transitional forms and the Fishapod...


Friday, July 06, 2007

Spots 'n Stripes

A student, Raj, sent me a link to this amazing image of a Horse-Zebra cross. The article calls it a Zebrula and if you check Wikipedia you'll see there are a number of Zebra crosses, collectively known as Zebroids:

Zebra (stallion) + horse (mare): zorse, zebra mule, zebrule or golden zebra
Zebra (stallion) + pony (mare): zony
Zebra (stallion) + Shetland pony (mare): zetland
Zebra (stallion) + any ass species (jenny): zebrass
Zebra (stallion) + donkey (jenny): zedonk, zeedonk, zonkey, zebronkey, zebadonk
Zebra (mare) + donkey (sire): zebrinny
Zebra (mare) + horse (stallion): hebra

Apparently they were mentioned by Darwin: in the Origin of Speies he refers to four coloured drawings of hybrids between the ass and zebra. These crosses are usually sterile. The Zorse article has some comments on genetics:

Zebras, donkeys, and horses are all members of the family equus -- equines. Equines can be crossbred to produce hybrids. They are all slightly different in genetic makeup, but still all equines. That is, horses have 64 chromosomes, zebra have between 44 and 62 (depending on species). Zorses can be male or female, but are sterile since their chromosome count is 63.

Just in case you think I get all my information from Wikipedia I'll also refer you to the wonderfully named International Zebra-Zorse-Zonkey Assocation. Lots of information and pictures and even a Zonkey for sale. Where else but at the Spots 'n Stripes Ranch in California. I didn't know I wanted a Zonkey, but now I do.

This time last year: The map that changed the world


Thursday, July 05, 2007

Species diversity

A nice overlap between evolution and ecology is the concept of species diversity. Studying what causes the number of species in a group to increase or decrease is largely the realm of evolution and studying what allows a particular number of species to coexist in any particular habitat is largely the realm of ecology. However, when species get affected by man and are driven to extinction the subject is often of interest to both evolutionary biologists and ecologists.

A nice study reported this week shows that although the loss of species diversity of Tahiti's snails has been high (following the introduction of a predatory snail), the diversity at a larger scale remains because members of each of the major groups (or clades) remain.

'Not much of a consolation, perhaps, but at least in a few hundred thousand years there might once again be the kind of diversity on Tahiti that existed before we arrived.'

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Wednesday, July 04, 2007

High-performing males have underachieving daughters

An interesting article in Nature last week, summarized here, described how, in red-deer, successful fathers tend to have unsuccessful daughters. In contrast male deer that carried genes that led to greater success in daughters were less successful themselves. This provides an interesting insight into the so called 'battle of the sexes' and may help explain why some genetic variation is maintained in sexual species.

This is relevant to our discussion of sexual selection but we will also return to this topic in the ecology section when we talk about different mating strategies.

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Another June has gone by

Last year I tried to keep this blog class related. I think my only significant lapse was on the 4th of July, so now I'll repeat that with a link to one of my favorite songs. Last year I couldn't find a copy to link to but this year there is a video of Aimee Mann singing 4th of July on Jools Holland's TV show. Enjoy.

This time last year: 4th of July


Tuesday, July 03, 2007

Scientists change one species to another (cue evil laugh)

Scientists, oh those wacky scientists, have now transformed one species into another. Craig Venter and his team took the genome of one bacteria and transplanted into another, thus changing it to another species. This research is being reported as the first step in creating an artificial life form from scratch. You can read a BBC report, a report in New Scientist magazine or listen to Ira Flatow talk to Craig Ventner on last week's NPR's Science Friday.

This time last year: follow up on some of the examples from class, Coevolution and Speciation Examples.

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Monday, July 02, 2007

Resistance is not so futile

I could probably post a new link about antibiotic resistance every day. Here's one I noticed today, a report by NPR that Chinese fish imports may contain fluoroquinolone antibiotics - a potentially serious problem since ciprofloxacin, currently often used a last resort, is a fluoroquinolone. You may remember ciprofloxacin, or Cipro, as the drug of choice during the 2001 anthrax attacks.

Some of you may have seen the press reports last week following a new survey of US hospitals that revealed much higher levels of antibiotic resistant bacteria than previously suspected.

Here's a previous post on this topic: Losing the Battle

This time last year: Heterozygote Advantage

and here's a post from approximately this time last year that someone was asking about. Are humans still evolving: Got Milk?

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Sunday, July 01, 2007

Only vaguely related

One of the joys of the weekend is catching up on some reading. Although I'm a great fan of the internet I also love magazines. An article in Wired magazine (also available online here) on the advantages humans still hold over computers made me smile. Sometimes people are real smart. You know those little distorted strings of numbers and letters you have to type in on some sites to prove you aren't a robot? Well apparently they are called captchas (Completely Automated Public Turing Test to Tell Computers and Humans Apart). But the next generation of them will be in two parts. The first will be the actual test (which the computer knows the answer to) but the second will be something that couldn't be deciphered by the Internet Archive's project to scan public domain books (a smudged or faded word perhaps). So in the course of everyday transactions millions of people will be helping to correct machine read text. Cool.

Also, in The Week magazine, a weekly compendium of the best US and International journalism, I came across this quote by John Kenneth Galbraith:
"Faced with the choice between changing one's mind and proving that there is no need to do so, almost everyone gets busy on the proof."

This time last year: Family History