Martin Krzywinski / Genome Sciences Center / mkweb.bcgsc.ca Martin Krzywinski / Genome Sciences Center / mkweb.bcgsc.ca - contact me Martin Krzywinski / Genome Sciences Center / mkweb.bcgsc.ca on Twitter Martin Krzywinski / Genome Sciences Center / mkweb.bcgsc.ca - Lumondo Photography Martin Krzywinski / Genome Sciences Center / mkweb.bcgsc.ca - Hilbertonians - Creatures on the Hilbert Curve
Poetry is just the evidence of life. If your life is burning well, poetry is just the ashLeonard Cohenwatch

a rat: fun


Visualization Tour, Melbourne, October 9–20, 2014


Alex — Internet's Most Popular Rat

Poster Rat for Rat Genome Sequencing

The rat genome sequencing project at the Baylor College of Medicine Human Genome Sequencing Centre is complete. The genome has been analyzed and published.

I'd like to introduce you one of the faces of the project: Alex, the genomics rat idol.

Arguably, Alex is the most popular rat on the internet. For the justification of this strong statement, read on.

rat (Rattus norvegicus) on genome sequencer - alex on an abi 3700 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Alex, the rat. Rattus norvegicus on an ABI 3700 genome sequencer. (zoom)
rat (rattus norvegicus) on genome sequencer - alex on an abi 3700 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Alex, the rat. Rattus norvegicus on an ABI 3700 genome sequencer. (zoom)

Alex's Biography

Alex was born in May 2000. It's well known that a rat's cuteness reaches maximum at about 3-4 weeks. After this critical time, a pet store rat is less likely to be purchased and may be asked to act as snake food. In Alex's case, she was perilously close to her deadline. Luckily for her, we paid a ransom of $6.99 to the Noah's Ark pet shop in Vancouver. She was on her last cute leg.

Portrait of Alex, the genome rat (Rattus norvegicus). / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Portrait of Alex, the genome rat (Rattus norvegicus). Here, she is seen in a forced portrait position (zoom)

From May 2000 Alex spent most of her time hoarding food pellets and riding on shoulders.

Portrait of Alex, the genome rat (Rattus norvegicus). Riding on shoulder. / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Portrait of Alex, the genome rat (Rattus norvegicus). Riding on shoulder.

Alex liked to bite. And rats only bite hard — they don't nibble. Her contention for this unattractive behaviour was the uncanny similarity between a finger and a pellet of food.

Other than unpredictable bouts of biting (by far the most exciting aspect of her personality), Alex lacked other distinguishing characteristics.

Alex died of a seizure in late 2002. She was buried outside of the Museum of Anthropology. A ratty pair of underwear served as a burial shroud.

And I hope you got that last pun.

DOWNLOAD ALL PHOTOS.

Photos are for public use. Use, modification and distribution of these photos is unrestricted.

Alex's Popularity

Despite my best efforts at meaningful work, this web page continues to be the most popular of all my online offerings, making for a somewhat embarrassing achievement.

Alex's images consistently show up first in Google's web search for 'rat', 'rat image' and image search for 'rat'.

Portrait of Alex, the genome rat (Rattus norvegicus). / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Alex image is the first for Google's 'rat' search query (retrieved 16 Mar 2013). (rat Google search)
Portrait of Alex, the genome rat (Rattus norvegicus). / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Alex image is the first for Google's 'rat image' search query (retrieved 16 Mar 2013). (rat Google search)

Finally, Alex appears as the first entry in Google images for 'rat'.

Portrait of Alex, the genome rat (Rattus norvegicus). / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Alex image is the first for Google's 'rat image' search query (retrieved 16 Mar 2013). (rat Google search)

Alex's Public Appearances

Alex is neither without modesty nor public fame. Her first cover-ratgirl appearance was on the April 2004 issue of Genome Research.

Rat Issue of Genome Research, April 2004 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Alex the rat appeared on the cover of Genome Research (April 2004). (zoom)

More recently, she's appeared on the cover of Ethnologie Francaise (Jan-Mar 2009 issue).

Alex the rat on the cover of Ethnologie Francaise (1/2009) / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Alex the rat appeared on the cover of Ethnologie Francaise (1/2009). (zoom)

The topic of the issue was the relationship between animals and humans. It is fitting therefore to recount here the relationship I shared with Alex during her sojourn with us.

news + thoughts

Nested Designs—Assessing Sources of Noise

Mon 29-09-2014

Sources of noise in experiments can be mitigated and assessed by nested designs. This kind of experimental design naturally models replication, which was the topic of last month's column.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Nature Methods Points of Significance column: Nested designs. (read)

Nested designs are appropriate when we want to use the data derived from experimental subjects to make general statements about populations. In this case, the subjects are random factors in the experiment, in contrast to fixed factors, such as we've seen previously.

In ANOVA analysis, random factors provide information about the amount of noise contributed by each factor. This is different from inferences made about fixed factors, which typically deal with a change in mean. Using the F-test, we can determine whether each layer of replication (e.g. animal, tissue, cell) contributes additional variation to the overall measurement.

Krzywinski, M., Altman, N. & Blainey, P. (2014) Points of Significance: Nested designs Nature Methods 11:977-978.

Background reading

Blainey, P., Krzywinski, M. & Altman, N. (2014) Points of Significance: Replication Nature Methods 11:879-880.

Krzywinski, M. & Altman, N. (2014) Points of Significance: Analysis of variance (ANOVA) and blocking Nature Methods 11:699-700.

Krzywinski, M. & Altman, N. (2014) Points of Significance: Designing Comparative Experiments Nature Methods 11:597-598.

...more about the Points of Significance column

Replication—Quality over Quantity

Tue 02-09-2014

It's fitting that the column published just before Labor day weekend is all about how to best allocate labor.

Replication is used to decrease the impact of variability from parts of the experiment that contribute noise. For example, we might measure data from more than one mouse to attempt to generalize over all mice.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Nature Methods Points of Significance column: Replication. (read)

It's important to distinguish technical replicates, which attempt to capture the noise in our measuring apparatus, from biological replicates, which capture biological variation. The former give us no information about biological variation and cannot be used to directly make biological inferences. To do so is to commit pseudoreplication. Technical replicates are useful to reduce the noise so that we have a better chance to detect a biologically meaningful signal.

Blainey, P., Krzywinski, M. & Altman, N. (2014) Points of Significance: Replication Nature Methods 11:879-880.

Background reading

Krzywinski, M. & Altman, N. (2014) Points of Significance: Analysis of variance (ANOVA) and blocking Nature Methods 11:699-700.

Krzywinski, M. & Altman, N. (2014) Points of Significance: Designing Comparative Experiments Nature Methods 11:597-598.

...more about the Points of Significance column

Monkeys on a Hilbert Curve—Scientific American Graphic

Tue 19-08-2014

I was commissioned by Scientific American to create an information graphic that showed how our genomes are more similar to those of the chimp and bonobo than to the gorilla.

I had about 5 x 5 inches of print space to work with. For 4 genomes? No problem. Bring out the Hilbert curve!

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Our genomes are much more similar to the chimp and bonobo than to the gorilla. And, we're practically still Denisovans. (details)

To accompany the piece, I will be posting to the Scientific American blog about the process of creating the figure. And to emphasize that the genome is not a blueprint!

As part of this project, I created some Hilbert curve art pieces. And while exploring, found thousands of Hilbertonians!