As zoos’ goals, designers’ values, and guests’ expectations change, so do the structures seen at the zoo. Exhibit history is not clear cut, and – despite what some may claim – is not inherently linear. Exhibit strategies develop as a result of tensions, both social and operational, imposed from both inside and outside of zoos. This literature review examines the history of zoo architecture by defining six design periods and considering the lenses of race, class, and nature.

People have known about mass biodiversity loss and the human actions that drive it for decades now, and yet we have largely failed levels to change our behavior to protect the environment. What’s failing to motivate people to change? Some conservation psychologists have partially blamed the negative way we communicate about environmental issues for paralyzing audiences into doing nothing because they feel helpless to change such a big problem. Instead, many psychologists have called for using positive emotions in communication to motivate an audience, but there’s still little research showing whether that’s a more effective approach or not. To study whether positive or negative emotions are really more motivational for inspiring change, I looked at how different emotions were used in the discourse about an emerging conservation technology called de-extinction as a case study. De-extinction claims to be both a tool for fighting biodiversity loss and for inspiring more positive and inspiring narratives in conservation. In this thesis, I examine those claims by exploring five emotions that the discourse around de-extinction elicits: fear, guilt, grief, awe and hope. I examined the motivating power of those emotions and what kind of actions de-extinction discourse motivates or fails to motivate through the way it uses those emotions. I found that de-extinction discourse erases negative emotions and boosts positive ones as many conservation psychologists recommend. However, de-extinction discourse accomplishes this in misleading ways: it minimizes the sense of importance of ongoing extinctions by framing extinction as a reversible phenomenon, and it overstates the ability of technology alone to combat the extinction crisis without requiring societal change. As a result, de-extinction discourse could risk making the public less motivated to take personal action to forward conservation goals. I conclude that positivity or negativity should not be the central concerns for motivating action, but rather efficacy and honesty.

With issues such as environmental degradation, climate change, and mass extinction looming, a growing coalition of activists, policymakers, lawyers, scholars, and everyday people are calling for the Rights of Nature to be legally recognized in order to create systemic changes in environmental policy. This thesis traces the history of the Rights of Nature movement, examining key developments around the world and analyzing the historical and ethical underpinnings of these provisions, and how the Rights of Nature can be applied to the Endangered Species Act in the United States. Evoking the language of legal rights has pragmatic value in U.S. environmental policy, explicitly stating the non-anthropocentric position of intrinsic value of nature in an effort to push for a broader value shift within a predominantly anthropocentric legal system.

George McDonald Church studied DNA from living and from extinct species in the US during the twentieth and twenty-first centuries. Church helped to develop and refine techniques with which to describe the complete sequence of all the DNA nucleotides in an organism's genome, techniques such as multiplex sequencing, polony sequencing, and nanopore sequencing. Church also contributed to the Human Genome Project, and in 2005 he helped start a company, the Personal Genome Project. Church proposed to use DNA from extinct species to clone and breed new organisms from those species.

During the twentieth and twenty-first centuries, Robert Paul Lanza studied embryonic stem cells, tissues,
and endangered species as chief scientific officer of Advanced Cell
Technology, Incorporated in Worcester, Massachusetts. Lanza's team cloned
the endangered species of gaur Bos gaurus.
Although the gaur did not survive long, Lanza successfully cloned
another cow-like creature, called the banteng
(Bos
javanicus). Lanza also worked on cloning human embryos
to harvest stem cells, which could be used to treat dieases. While
previous techniques required the embryo's destruction, Lanza
developed a harvesting technique that does not destroy the embryo,
forestalling many ethical objections to human embryonic
research.

The Southern Gastric-Brooding Frog (Rheobatrachus silus) was an aquatic frog that lived in south-east Australia. In 2002, the International Union for Conservation of Nature Red List declared the frog extinct, although no wild specimens had been reported since 1981. As the common name alludes to, the R.
silus was a gastric-brooder, meaning that the female's eggs developed inside of her stomach. Weeks after ingestion, juvenile frogs escape through the mother's mouth. Because no other observed species performs this reproductive behavior, in the early twenty-first century R. silus became a target of
the de-extinction movement that aims to resurrect extinct species. Researchers studied this frog's reproductive behavior and how the eggs and embryos escape digestion. Some scientists claimed that resurrecting this frog could result in future medical applications related to digestion and to reprogramming organ function, as during pregnancy, R. silus's stomach physiologically functioned as a uterus.