Notes on Scientific Method, Mass Extinction Context, and Invasive Snail Case Study

African Giant Land Snail (Achatina fulica)

An invasive species introduced as a food source that became a crop pest.

American Rosy Wolf Snail (Euglandina rosea)

A second invasive species introduced as a biological control agent to prey on the African Giant Land Snail, with the risk of becoming an unintended pest itself.

Mass Extinction

A period in which a substantial portion of biodiversity goes extinct across many taxa in a geologically short interval (e.g., a century or so), often discussed as five major events in Earth history. Can be distinguished between natural and human-caused.

Poaching

Illegal hunting or harvesting of wildlife.

Science

A body of knowledge and the systematic process of acquiring knowledge about how the natural world works and what can be known about it.

Evidence-based Reasoning

Claims supported by measurable observations and data, requiring broader data sets and replication, not solely by personal experience or anecdotes.

Scientific Method

A structured approach where observations lead to questions, which motivate hypotheses, guiding experimental design, yielding results for analysis, interpretation, and conclusions, often followed by further testing and replication.

Hypothesis

A testable prediction or explanation for an observation, which guides experimental design.

Reproduction Rate (R)

The rate at which organisms reproduce, typically defined as the number of offspring produced per individual per unit time, formalized as R = \frac{E}{t}, where $E$ is the number of eggs/offspring and $t$ is the time interval.

Proving a Negative

Generally impossible in science; hypotheses about absence must be reframed as probabilities or require extensive sampling to support a strong claim of absence rather than definitive proof.

African giant land snail (Achatina fulica)

An invasive species introduced as a food source, which became a significant crop pest in the case study.

American rosy wolf snail (Euglandina rosea)

A second invasive species introduced as a biological control agent to prey on the African giant land snail, with the risk of becoming a new ecological problem due to its own invasiveness.

Biological control agent

An organism introduced to prey on or control a pest species, often carrying the risk of unintended ecological consequences.

Mass Extinction

A period characterized by five major historical events during which a substantial portion of Earth's biodiversity is lost rapidly (e.g., within a century) across many taxa.

Anthropogenic factors

Human-caused factors, such as habitat destruction and emissions, that contribute to rapid biodiversity loss.

Poaching

The illegal killing or harvesting of wildlife, distinct from everyday, legal activities.

Science

A body of knowledge and the systematic process of acquiring knowledge about how the natural world works, involving systematic inquiry, observations, and measurements.

Evidence-based reasoning

Claims supported by measurable observations and data, requiring broader data sets and replication, not solely personal experience or anecdotes.

Anecdotal evidence

Information gathered from a single observer's experience, which is considered insufficient for scientific generalizations or conclusions.

Scientific Method (Core Process)

A structured approach where observations lead to questions, which motivate hypotheses that guide experiments. Results are analyzed to test hypotheses, leading to conclusions that may be supported or revised through further testing and replication.

Hypothesis

A testable prediction or proposed explanation for an observed phenomenon that guides the design of experiments or observational studies.

Peer validation

The process by which independent scientists verify and reproduce findings, which is a prerequisite for turning a result into accepted knowledge.

Reproduction rate

The rate at which organisms reproduce, typically defined as the number of offspring produced per individual per unit time, which can influence population growth and invasion success.

Proving a negative

The conceptual difficulty in science of definitively proving that something does not exist everywhere and at all times; hypotheses about absence are typically reframed as probabilities or require extensive sampling.

Reproduction Rate Formula

R = rac{E}{t} where E is the number of eggs laid (or offspring produced) and t is the time interval.