Potential Datasets For Projects

We want practice with real-world data sets that are the appropriate to build our skills. I strongly believe the best data sets are one you care about / are invested in. But not all of you have those. Here are some data sets for you if you don’t have any data sets that you’re invested in.

29.3 Previous examples that should work

Salmon size

After approximately three years as babies salmon become mature and are ready for the ocean. Hendry et al, measured the mass and length of female salmon who have been in the ocean for two or three years. The data are here. data, paper.

Chip off the old block

There are many hypotheses for the evolution of sexual selection. One such hypothesis is the sexy son theory - a somewhat circular (but not illegitimate) argument that females gain an evolutionary advantage by mating with attractive males because those males will give rise to attractive sons that will have success with other females. This theory requires a association between dad and son sexual attractiveness. Brooks measured the attractiveness of father-son pairs of male guppies (by evaluating female’s preference for them). data, paper.

Life at high altitude

Living at high altitude represents some physiological challenges of living with a limited oxygen supply. Human populations in the Andes, Ethiopia, and Tibet have faced these challenges, and adapted. One potential mechanism of this adaptation is to raise the hemoglobin content of blood to get more oxygen. Beall et al measured the hemoglobin content of people from these three populations as well as a control of males living at sea level in America. data, paper.

A mountain in Tibet from the [New York Times](https://www.nytimes.com/2011/03/06/books/review/Becker-t.html)

Figure 29.1: A mountain in Tibet from the New York Times

Eat leas, live longer?

For some reason, restricting food intake often increases lifespan.To see if this was the case, Mattison et al fed 17 rhesus monkeys (7 females, 10 males) a reduced diet with 30% of the normal nutrition, and 17 other rhesus monkeys (8 females, 9 males) a normal nutritious diet. data, paper.

Fruit and photosynthesis

To investigate if previous reproductive efforts impact subsequent growth and photosynthesis, Wheelright and Logan looked at the previous number of fruits and the photosynthetic activity of nine female Ocotea tenera trees - a neotropical species. data, paper.

Image of  *Ocotea tenera* from wikimedia commons

Figure 29.2: Image of Ocotea tenera from wikimedia commons

A gene for monogamy?

The gene for the vasopressin receptor V1a is expressed at higher levels in the forebrain of monogamous than promiscuous vole species. To see if expression of this gene influenced monogamy, Lim et al experimentally enhanced V1a expression in the forebrain of 11 males of the meadow vole - a solitary promiscuous species, and compared the percentage of time these and control males spent huddling with a female placed with him (as a measure of monogamy). data, paper.

Image of cuddling voles from  [Newsweek](https://www.newsweek.com/fall-love-brain-circuits-involved-prairie-voles-618111)

Figure 29.3: Image of cuddling voles from Newsweek

Running with a lighter load

Male spiders in the genus Tidarren are tiny and weigh about 1 percent as much as females. Just before sexual maturity, males voluntarily amputate one of their two organs just before sexual maturity. Could this maybe allow them to move faster? data, paper.

Image of Tidarren from  [Ramos et al.](https://www.pnas.org/content/101/14/4883) Their legend *A male T. sisyphoides before (A) and after (B) removing a pedipalp. Note the pedipalps overlap in the two-pedipalp condition (A), whereas the one pedipalp is carried in a central position after pedipalp removal (B). (The scale bars represent 1 mm.)*

Figure 29.4: Image of Tidarren from Ramos et al. Their legend A male T. sisyphoides before (A) and after (B) removing a pedipalp. Note the pedipalps overlap in the two-pedipalp condition (A), whereas the one pedipalp is carried in a central position after pedipalp removal (B). (The scale bars represent 1 mm.)

Protected fish

The marine threespine stickleback is a small coastal fish named for its defensive armor. It has three shrp spines on its back, two pelvic spines under its belly and a series of lateral bony plates down its side.The armor seems to reduce mortality from predatory fish and diving birds. In lakes and stream (as compared to the ocean) there are fewer predators, and fish have reduced armor. Researchers hypothesized this difference may mediated by a gene called ectodysin. They crossed marine (M) and freshwater (m) fish to make F1 Mm heterozygotes and crossed these to one another two make individuals who have 0 (mm), 1 (Mm), or 2 (MM) copies of the marine allele at the ectodysin locus. data, paper.

Image of benthic and marine sticklebacks (from [oceanbites](https://oceanbites.org/little-fish-new-pond-watching-stickleback-evolution-in-real-time/)

Figure 29.5: Image of benthic and marine sticklebacks (from oceanbites