Question

As readers of Herman Melville's 1851 novel Moby Dick know, at one time oil made from whale blubber was an important source of energy that was widely used by households and firms in oil lamps. Other sources of energy replaced whale oil in the second half of the nineteenth century, and today many Americans consider whales only as a source of entertainment on visits to aquariums and whale watching excursions. But some species of whales-including baleen and gray whales - are in danger of extinction. The U.S. Department of Agriculture estimates that more than 9 billion chickens are raised for food annually. Chickens, unlike whales, are not threatened with extinction. Briefly explain why.

Short answer

Whales and chickens have different roles in human society and different reproduction rates. Whales, once used for oil production, were over-hunted, and due to their slow reproduction rate, their population hasn't completely recovered even after the decrease in demand. Chickens are raised for food, a resource with constant demand, but due to their fast maturity and reproduction rate, their population remains sustained, preventing the risk of extinction.

Step-by-step solution

Identify the Roles of the Species in Human Society

Whales were hunted for their blubber, which was used to produce oil, a source of energy. This resource has been replaced by other energy sources in the modern era. In contrast, chickens are being raised for their meat, a food resource, which remains in high demand today.

Understand the Reproduction Rates of the Species

Whales typically have long lifespans, extended maturity periods, and low birth rates, so their population can recover only slowly from the impact of whaling. Chickens, on the other hand, mature quickly and reproduce rapidly, allowing for their population to be sustained even with high usage rates.

Apply Economic Principles

Economic principles of supply and demand play a key role in this situation. The demand for whale oil decreased over time and was replaced with other energy resources, reducing the hunting of whales. However, because of their slow recovery rate, the whale population remains threatened. In contrast, the demand for chicken meat remains high, but due to their fast reproduction rates, the supply is consistently available, and chickens are not at risk of extinction.

Key concepts

Supply and Demand

Supply and demand are fundamental economic principles that play a pivotal role in determining market prices and availability of resources. Historically, whale blubber was in high demand as it was a crucial source of oil used in lamps. As demand increased, the supply of whales in the ocean began to dwindle due to overhunting.
Eventually, with technological advancements, alternative energy sources like kerosene replaced whale oil, leading to a sharp decline in demand for whale blubber. This decline in demand effectively reduced the hunting pressure on whale populations. However, because whales reproduce very slowly and other critical factors, their populations remained at risk.
On the other hand, the demand for chicken meat has consistently remained high due to its status as a staple food in many diets worldwide. The supply of chickens is readily maintained because they reproduce quickly. This balance between high demand and sustainable supply ensures that chickens remain abundant and are not threatened with extinction.
Understanding how supply and demand affect resource availability can help inform conservation strategies and sustainable resource management.

Resource Sustainability

Resource sustainability involves using resources at a rate where they can naturally replenish. It is a critical concept for ensuring that species and resources are available for future generations. Overhunting whales for their blubber created an unsustainable environment, endangering their existence. Without sufficient recovery time, whale populations struggled to rebound from extensive hunting.
The switch to alternative energy sources lessened the immediate pressure on whale populations, but the damage had been done. This presents a classic case of unsustainability, where exploiting a species faster than it can recover jeopardizes its survival.
On the contrary, modern agricultural practices have developed methods to sustainably produce chicken meat. By prioritizing rapid breeding and growth rates, chicken farms maintain a steady supply without over-exhausting the population. This is a sustainable practice because it aligns the rate of consumption with the pace of reproduction.
Focusing on sustainability allows us to manage resources prudently, preserving ecological balance and preventing species extinction.

Species Reproduction Rates

Species reproduction rates significantly impact their ability to withstand external pressures like hunting and habitat loss. Whales reproduce at a slow rate—they have lengthy gestation periods and typically give birth to one calf at a time. This low birth rate means any reduction in population due to hunting is difficult to replenish quickly.
Conversely, chickens have notably high reproduction rates. They become mature within months and can lay multiple eggs at frequent intervals. This rapid reproductive cycle enables chicken populations to remain stable and recover swiftly from human consumption.
High reproduction rates in chickens, combined with protective farming practices, allow for their continual availability without the risk of extinction. Meanwhile, whales serve as an example of why understanding species reproduction is key to managing and conserving wildlife effectively.
Managing species with slower reproduction rates requires careful consideration and protective measures to ensure their populations remain viable despite external threats.