# data[].attributes.body
Photo taken by author at Saginaw Children's Zoo in Saginaw, MI.

# data[].attributes.body
Wikimedia Commons. (2011). Trophic Levels. Retrieved from https://commons.wikimedia.org/wiki/File:Trophiclevels.jpg

# data[].attributes.body
Theme Pluto. (2014).

Information about Stable Carbon and Nitrogen Isotope Analysis. Retrieved from http://syromonoed.com/information-stable-carbon-nitrogen-isotope-analysis/

# data[].attributes.body
Ormond, B. (2014). Isotopes used in agriculture. Thinglink. Retrieved from https://www.thinglink.com/scene/489855285981085697.

# data[].attributes.body
Principles of Chemistry. Retrieved from http://faculty.csupueblo.edu/linda.wilkes/111/2a.html

# data[].attributes.body
Weber, R.L. (2011). African penguins battle extinction. PRI. Retrieved from https://www.pri.org/stories/2011-06-19/african-penguins-battle-extinction.

# data[].attributes.body
Loudon, J.E., Sponheimer, M. (2016). Conservation: new potential for stable isotope analysis? Ethnoprimatology, 399-414.

# data[].attributes.body
USGS: Science For a Changing World. (2006). You are what you eat. Retrieved from https://wwwrcamnl.wr.usgs.gov/isoig/projects/fingernails/results/interpretdata.html.

# data[].attributes.body
Russo, G., Danieli, P.P., Primi, R., Amici, A., Lauteri, M. (2017). Stable isotopes in tissues discriminate the diet of free-living wild boar from different areas of central Italy. Plos one, 12, 1-11.

# data[].attributes.body
McKechnie, A.E. (2004). Stable isotopes: powerful new tools for animal ecologists. South African Journal of Science, 100, 131-134.

# data[].attributes.body
Miller, S. (2012). Isotopes in feces shed light on gorillas’ diet. Nature World News. Retrieved from http://www.natureworldnews.com/articles/379/20121212/isotopes-feces-shed-light-gorillas-diet.htm.

# data[].attributes.body
Malainey, M.E. (2010). Isotope Analysis. A Consumer’s Guide to Archaeological Science, 177-200.

# data[].attributes.body
Machicek, M. (2013).Isotope Analysis. Cornell University. Retrieved from http://www.pbs.org/time-team/experience-archaeology/isotope-analysis/.

# data[].attributes.body
DeNiro, M.J., Epstein, S. (1978). Influence of diet on the distribution of carbon isotopes in animals. Geochimica et Cosmochimica Acta, 42, 495-506.

# data[].attributes.body
Chisholm, B.S., Nelson, D.E., Schwarcz, H.P. (1982). Stable-carbon isotope ratios as a measure of marine versus terrestrial protein in ancient diets. Science, 216, 1131-1132.

# data[].attributes.body
Carreon-Martinez, L., Heath, D.D. (2009). Revolution in food web analysis and trophic ecology: diet analysis by DNA and stable isotope analysis. Molecular Ecology, 19, 25-27.

# data[].attributes.body
Carr, E. (2016). Stable Isotope Analysis. SlidePlayer. Retrieved from http://slideplayer.com/slide/5914189/.

# data[].attributes.body
My A.I.P. master plan will be focused on animal conservation. One example of how stable isotope analysis is currently being used in animal conservation involves non-human primates. By comparing stable isotope compositions of existing primate populations to museum specimens, researches have documented geographic variation in diet and linked it to local vegetation and investigated dietary change over time (Loudon & Sponheimer, 2016). According to Loudon & Sponheimer (2016), primatologists have also applied stable isotope analysis to compare the diets of primate groups with varied access to human foods.

Stable isotope analysis provides insight toward research of non-human primate behavior, for example, the isotope technology is able to detect cryptic feeding patterns such as crop raiding by non-human primates (Loudon & Sponheimer, 2016). Through further usage of stable isotope analysis in conservation estimates of the contributions of particular foods to a species diet, dietary data for hard to observe (nocturnal) species, and comparative work amongst fossil relatives can all over insight to animal conservation and ecology over time (Loudon & Sponheimer, 2016).

If stable isotope analysis could be applied to African penguins (Spheniscus demersus) perhaps scientists could defend the conservation theory that, due to over-fishing and climate change, the birds are left to swim further out to sea or with less nutritious diet options. Pelagic fish, such as anchovies and sardines, typically make up an African penguins main diet; however, the populations of pelagic fish are declining due to raising water temperatures correlated with climate change (Weber, 2011). Perhaps through these efforts the ultimate goal would be that we also create further ways to conserve.

# data[].attributes.body
Because of the direct relationship between the type of food being consumed and the corresponding isotopic "signature" found in bone collagen of animals, isotopes can be used to assess diet (PBS, 2013).

Example:
If a cow eats some "grass type X", they will exhibit an isotopic value in their bones or teeth that will then represent "grass type X". (PBS, 2013).

According to PBS (2013), the isotopic values within individual animals will situate them inside a particular trophic level; it's place in the food chain.
Figure 4:

# data[].attributes.headline
Comparing a Single Species in Multiple Habitats

# data[].attributes.subject
Comparing a Single Species in Multiple Habitats

# data[].attributes.body
The wild boar (Sus scrofa) is the only non-ruminant ungulate with a three-glandular stomach, similar to mammals (Russo et al., 2017).

According to Russo et al. (2017), it is an omnivorous species and its diet depends on the available food resources: in winter, vegetables (acorns, roots, tubers, chestnuts) represent most of the total food mass (80–90%), while food of animal origin, such as arthropod larvae, annelids, micro-mammals or remains is consumed throughout the year but mainly in winter; considering the crops, corn (Zea mays) is an important and dominant part of the diet for wild boar in Europe.

The research in this study demonstrates that both carbon and nitrogen isotope compositions in free-living wild boar tissues are affected by the sampling area, in which three various locations were referenced (Russo et al., 2017).

According to feeding habits of the species and management regimes of the areas, the observed differences of δ13C and δ15N are based on the specific feeding regime, with particular evidence related to the use of corn (Russo et al., 2017).

This type of research allows individuals to study diet trends within one species in various geographical locations. From this, we could potentially tie in more information to understanding animal adaptions and conservation of species.

# data[].attributes.body
Ongoing change in the environment is inevitable, especially in the face of new environmental challenges such as climate change or invasive species (Carreon-Martinez & Heath, 2009).

Characterizing predator-prey interactions through isotope analysis is a very important component of ecosystem-level studies, particularly because some species will modify their diet in response to environmental change or perturbation (Carreon-Martinez & Heath, 2009).

Through the use of isotope analysis in animals to study predator-prey relationships, conservation science could greatly benefit.

If just one member of a food chain disappears, other species are also effected.

# data[].attributes.headline
Using Feces Samples for Isotope Analysis of Animal Diet

# data[].attributes.subject
Using Feces Samples for Isotope Analysis of Animal Diet

# data[].attributes.body
Miller (2012) explains that a team of researchers carried out a study to find out what the wild mountain gorillas in Uganda's Bwindi Impenetrable National Park ate over a period of one year.

This information could offer insight as to how the animals adapt and survive in changing environments (Miller, 2012).

From 2002-2003, samples of feces from gorillas were collected.

The samples were subjected to chemical analysis, revealing the isotopes of the food consumed by the apes.

Research showed that the Ugandan gorillas consumed more fruits between February and March and then from June to July (Miller, 2012).
In order to analyze isotopes in animal bones, the animals must be captured or freshly deceased, while this technique shows an easy way to measure isotopes by collecting and analyzing feces (Miller, 2012).

Miller (2012) discusses that while this technique is easier to collect data from, it could not replace other isotope analysis techniques since it does not reveal specifically what foods were ate and the value of that specific food type.

The application of isotope analysis in this research works on a broader scale. If looking for seasonal trends in a specific species' diet, using feces samples in research would work efficiently and is typically easy to access for purposes of science.

# data[].attributes.body
Using stable-isotope ratios of animals does not require time-consuming behavioral observations, and provides information on assimilated, rather than ingested, material (McKechnie, 2004).

As mentioned by McKechnie (2004), because the turnover rates of tissues differ, stable isotopes can also be used to reconstruct diets over time scales ranging to years (bone collagen) to weeks and days (liver, blood plasma).

*See "applications in conservation" to learn that feces samples can also be used to some extent in isotope analysis for determining animal diet.

# data[].attributes.body
Information can be gained about diverse issues ranging from the diet and mobility patterns to the natural environment of an animal by using isotope analysis (Malainey, 2010).

With a gathering of this information on species, it is more likely that animals will receive the most up-to-date husbandry care when in captive scenarios and relates directly to conservation of animal species.

Pictured below is an African penguin, a member of the captive colony at the Saginaw Children's Zoo.
Figure 5:

# data[].attributes.body
Depending upon the sample and isotopes measured, isotope analysis has many potential benefits to science.

# data[].attributes.body
Within field studies it is assumed that herbivores will consume available plants at random, however, animals may be selective in their choice of food plants and the carbon values of the plants eaten may differ from the average carbon value of the plants available to the animal (DeNiro & Epstein, 1978).

# data[].attributes.body
It is possible that seasonal variation in the carbon isotopic composition of the diet occurs unless recently synthesized animal components are analyzed or an integrated value for the isotopic composition of the diet is used, the relationship between the plant and animal isotopic composition cannot be accurately determined (DeNiro & Epstein, 1978).

# data[].attributes.body
According to DeNiro & Epstein (1978), the accuracy with which the relationship between the carbon isotopic composition of an animal and its diet can be determined from samples collected in the field is limited by two factors which cannot be adequately controlled in such studies.

# data[].attributes.body
The growing availability of molecular genetic methods and data has fostered the use of PCR-based techniques to accurately distinguish and identify prey items in stomach, gut and fecal samples (Carreon-Martinez & Heath, 2009).

# data[].attributes.body
According to Carr (2016),

A diet high in C3 plants leaves behind low levels of 13C.

A diet high in C4 plants leaves high levels of 13C in bone collagen.

A diet high in marine foods products results in high levels of 13C, 15N, and 34S.

The differences in isotopic composition have been used to identify the relative contribution to an animal's diet of plants with varied photosynthetic pathways and of foods with marine vs. terrestrial origins (Chisolm et al. 1983).
Figure 3:

# data[].attributes.body
The international reference standard for nitrogen isotopes is nitrogen gas found in common air and changes very little from place to place and over time (USGS, 2006).

The international reference standard for carbon isotopes is VPDB, which is shorthand for "Vienna Pee Dee Belemnite" (USGS, 2006).

According to USGS, 2006, the original PDB sample was of fossilized shells of an extinct organism called a belemnite collected decades ago from the banks of the Pee Dee River in South Carolina; the original sample was used up long ago, but other reference standards were calibrated to that original sample.

We still report carbon isotope values relative to PDB but now use the term “VPDB” to indicate that the data are normalized to the values of that standard (USGS, 2006).

# data[].attributes.body
The isotope ratio values that are determined by analyzing an animal sample are compared to a "standard", specifically, we compare the ratio of the heavier to lighter isotope in the sample with the same ratio in the standard (USGS, 2006).

According to Malainey (2010), this analysis results in measurable differences between the food an animal consumes and the animal tissue formed from food components.

Stable-isotope ratios are expressed relative to element-specific standards using delta notation of the form δX, where X is the heavier of the two stable isotopes of the element of interest (McKechnie, 2004).

# data[].attributes.body
Atoms of a particular element that differ in their atomic masses, and do not decay with time (McKechnie, 2004).

When a sample is analyzed for isotope ratios, we are comparing the relative amounts of a "heavier" isotope and a "lighter" isotope to trace what was consumed (USGS, 2006).

Isotopes that are "stable" means that they are not radioactive.

For nitrogen, the heavy isotope is ¹⁵N and the light is ¹⁴N. For carbon, the heavy isotope is ¹³C and the light isotope is ¹²C.

Figure 2:

# data[].attributes.body
Atom:

Basic unit of matter

Composed of electrons, protons & neutrons

Element:

Pure substance

Contains 1 type of atom

Figure 1: