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16

Environment and Ecology

technologies—that is, transcriptomics and proteomics—to study the effects of toxic

substances on physiology, including metabolism, which should enable the mecha-

nisms of toxic action to be far more effectively determined. A rarer use of the term

is “the study of the response of the genome to toxic agent exposure”. ¹⁰

There are sufficient examples demonstrating that genes are not the sole determi-

nant of the toxicities of substances; environmental factors also play a role. ¹¹

For obvious reasons, there is far more toxicity data for nonhuman species (espe-

cially mice, rats, and zebrafish) than for humans. Given the growing amount of

genomic data for nonhuman species, sequence alignment can help to predict the tox-

icity of a substance actually measured in one species to other species. ¹² This is useful

not only for predicting human toxicity from data acquired using laboratory animals

but also for predicting toxicities of manufactured substances to many species found

in the natural environment.

Problem. Evaluate the relevance of epigenetics to toxicogenomics.

16.3

Ecosystems Management

Ecology is undoubtedly part of biology, and information science is increasingly

relevant to ecology. An especially modish activity is the analysis of time series of

salient environmental parameters (“leading indicators”) in order to give advanced

warning of imminent catastrophe. ¹³ Nevertheless, it is recognized that régime shifts

in ecological systems can occur with no warning, ¹⁴ as in the Bak–Sneppen model

of an evolving ecosystem (Sect. 4.1.2), and much rather laborious work has been

undertaken to demonstrate this point. Traditionally, this topic is a branch of general

systems theory (Sect. 12.1). An important rôle was played by Lotka and Volterra in

the early years of the twentieth century (the Lotka–Volterra model). ¹⁵ This work, in

fact, long predates the emergence of general systems theory as a distinct branch of

study (and may indeed have been its inspiration).

The search for “leading indicators” has by no means been abandoned. Indeed,

“the potential to identify early warning signals that would allow researchers and

managers to predict [e.g., the collapse of ecological communities] before they happen

has therefore been an invaluable discovery”. Nevertheless, the ultimate aims of this

search are far from clear. If the collapse were due to external (i.e., exogenous) forcing,

than indeed ecosystem “managers” might be able to do something about it (assuming

10 Marchant (2002).

11 For example, Povey (2010); see also Sect. 25.1.

12 The US Environmental Protection Agency (EPA) has developed an online software tool,

SeqAPASS, enabling toxicity information to be extrapolated across species.

13 Boettiger et al. (2013).

14 Hastings and Wysham (2010).

15 See the monumental review by Goel et al. (1971).