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Does anyone have any study recommendations for Ecology Division B for Wright State University? For reference I got 5th last year and I hope to do even better this year. Particularly something that goes in depth for Ecological principles and a resource for Conservational Biology as I am quite new to it.

From the practice tests that you guys have taken, which ones would you most recommend?

Alex-RCHS wrote:From the practice tests that you guys have taken, which ones would you most recommend?

I think it really depends on what tournament you're prepping for. For instance, if you were studying for MiT, which traditionally runs stations that emphasize vocab, a similar test would be helpful, such as Clements from this year. On the other hand, if you're expecting a long paper test, you'll be better off looking at tests such as Entymology's SSSS submission. Other than those, I liked Johns Creek and UGA, while Boca Raton was particularly well written.

What are the hardest type of questions out there? I've done Ecology many times, but it's always been so flat out easy, with one or two questions being the tipping point between getting 1st or 16th. Mainly, I feel that its luck on whether you know the answers to the hard questions (ex: if you intensely study a topic but then have no questions on given topic but get 3 hard questions on another topic). Does anyone have any advice? Thanks.

JoeyC wrote:What are the hardest type of questions out there? I've done Ecology many times, but it's always been so flat out easy, with one or two questions being the tipping point between getting 1st or 16th. Mainly, I feel that its luck on whether you know the answers to the hard questions (ex: if you intensely study a topic but then have no questions on given topic but get 3 hard questions on another topic). Does anyone have any advice? Thanks.

Honestly, I've seen a wide range of the questions some event supervisors put on their tests. Some are heavily conservation ecology based while others are population ecology based. Many of the tests I've seen have extremely hard vocabulary questions or ecology questions that you may have never heard of. This wide range makes it really hard to prepare and know what will be on the test.

hey, my friend wants to know what type of test this is, do you know?

Benewcomb wrote:hey, my friend wants to know what type of test this is, do you know?

It usually depends I think. If I'm reading your question right, it can be either a powerpoint, on paper, or stations. Questions can be short answers, multiple choice, fill in the blank, etc.

If you mean the test subject.. Well uh, ecology! The biome topics this year are Deserts and Grasslands. If you want to know other kinds of questions that can be given, I'd check out the event rules, as it gives examples of what you'd need to know.

The Kansas City Regionals exams -- both B and C divisions -- have been uploaded on the Test Exchange!

I wrote the exams, so comment here with any questions about the test, and I'll answer them.

Find the exams here: https://scioly.org/wiki/index.php/2018_ ... ge#Ecology

I'm having some trouble with a population growth question. Does anyone know how to solve it?

The smaller of the two herds is growing in a previously uncolonized area. The area is restricted in resources and as a result can only support 70,000 individuals. Presently, the herd numbers at only 12 thousand. With a generation time of 1 year, at time 3 years, the new population stands at 20,000 individuals. What is the maximum rate of growth?

Thanks so much!

gryphaea1635 wrote:I'm having some trouble with a population growth question. Does anyone know how to solve it?

The smaller of the two herds is growing in a previously uncolonized area. The area is restricted in resources and as a result can only support 70,000 individuals. Presently, the herd numbers at only 12 thousand. With a generation time of 1 year, at time 3 years, the new population stands at 20,000 individuals. What is the maximum rate of growth?

Thanks so much!

Given that generation time is given, this is probably a discrete logistic growth problem, so N_t+1 = N_t + N_t * r_0 * (1 - N_t/K). Assuming "time 3 years" to mean that 2 generations have elapsed, we have a system of equations to solve: x = 1200 + 1200 * r * (1 - 12000/70000) and 20000 = x + x * r * (1 - x/70000). From this I get x = 15604.3 and r = 0.3625. The maximum growth rate is at K/2 = 35000 individuals, so r * 35000 * (1 - 35000/70000) = 6344 individuals/year.

Instead assuming "3 years" to mean 3 generations I use a system of 3 equations to get r = 0.2339, generation N_t+1 to be 14326, generation N_t+2 to be 16991, and generation N_t+3 to be 20000. Observe that the change in N is increasing each generation. From this the maximum growth rate is 4093 individuals/year.

If we instead assume a continuous logistic model, we use the equation N_t = K/(1 + (K/(N_0 - 1)) * e^(-rt)) to solve for r. From this, I get r = 0.21975, so dN/dt = rN(1-N/K) at 35000 individuals is 3845.625 individuals/year.

I may be interpreting this question entirely the wrong way though ... is there an answer key or something? You can't do the first two equations at competition with a nongraphing calculator; WolframAlpha certainly makes it easier.