Predators, Prey, oh my!

Predators as "keystone" species

This week we've discussed how interactions among tropic levels affect community composition, specifically the role of top predators.  Key examples that we discussed in class include Robert Paine's work in the rocky intertidal zone of the pacific US with predatory seastars, and Jane Lubchenco's work examining how a predator affects algal diversity in New England tide pools (1978).

A great resource by Nature.com entitled "Species with a Large Impact on Community Structure" (2010) includes key terminology with mouse-over definitions to help you learn vocabulary associated with this section.  

Niche Differentiation & Competitive Exclusion

(Knowledge Project, Nature.com)

The figure (right) is an example of a species' fundamental niche, relative to their temperature and food requirements.  Learn more about how the environment affects species distribution here.

The figure (below) demonstrates the concept of competitive exclusion.  Competitively dominant species population (blue) will, in time, exclude the less dominant species (red) in areas where their fundamental niche overlaps.  In this example, the red species would then be confined to its realized niche.  However, if they divide resource - e.g., large seeds for blue, small seeds for red - the two species may coexist; this is termed niche differentiation.  

(Knowledge Project, Nature.com)

Learn more about niche partitioning, competition, and how they affect community diversity.

Light pollution and the environment

Lights at night by NASA

This week we've discussed a bit about light pollution, specifically how it affects Loggerhead sea turtles.  An easy to read article by ActionBioscience expands more upon the adverse effects of light pollution on wildlife, from insects to birds.

National Geographic produced the great video, below, of a Loggerhead turtle nest hatching, and their experience in the ocean during their swimming frenzy. 

8:30 pm, Saturday March 26th is Earth Hour.  

Earth Hour began in 2007 in Australia as an effort to raise awareness about climate change. Those who participate, turn their lights off for one hour, starting at 8:30pm. 

Happy World Water Day!

Because of increased demands and changes in climate patters, by 2050 a third of the people on Earth may lack clean, potable water.  

"The average American lifestyle is kept afloat by nearly 2,000 gallons of H2O a day—twice the global average."

What's your water use footprint?   

Take this quiz to find out approximately how much water you use every day.  My total score was 1,278 gallons/day, a bit better than the average American, but there is always room for improvement!

Neat water facts from National Geographic - 

how much water does it take to make....

• Wheat production accounts for 12% of world agricultural water use.
• 1,799 gallons of water are used to produce 1 lb. of beef. 
• 880 gal. water is used to create 1 gal. of cow's milk.
• 468 gal. of water are used to produce 1 lb. of chicken.
• It takes nearly 690 gal. of water to make 1 gal. of beer. 
• Over 1,000 gal. of water are used to make 1 gal. of wine. 
• One cotton t-shirt requires 713 gal. of water.
• 2.6 gal. of water is used to make one sheet of paper. 
• The making of a 0.3 lb hamburger uses over 650 gal. of water. 
• The supply chain for making one slice of bread requires 11 gal. 

Visit this National Geographic website to learn more about water conservation.

Field Report 2 DUE March 21 - Mon. after Spring Break!

Figure from UV Excel Tutorial Website

To ensure you have a fun and stress free spring break, and to make sure you do well on your next field report (most importantly), I would encourage you to get a head start on your report!

This second report (p.12 in your packet) does require some field work, math, and graphing.  

Those of you not familiar with Microsoft Excel, should review this website, which contains helpful tutorials.  They have tutorials for Excel 2003 and 2007 (2010 isn't much different from 2007).

Field report formatting requirements for Laura's sections: 

• 1-3 pages (more than 3 pages will not be read or graded!)
• 1 1/2" spacing
• 12pt Times New Roman or Arial font 
• 1 inch margins 
• Print double sided (preferred) 
• Stapled 
• Document header: name and section # 
• Document footer: page #