APES unit 3

• Types of species classifications

  • Generalist Species
  • Specialist Species
• Generalist Species

  Have a wide range of tolerance when it comes to food requirements and habitat needs, can utilize a ton of different food sources, survive in a ton of different habitats, and are really resilient
• Generalist Species

  • Raccoons
• Specialist Species

  Rely on a really narrow niche or a really unique set of habitat or food requirements
• Specialist Species

  • Pandas
• Reproductive strategies

  • Quantity over Quality
  • Quality over Quality
• Quantity over Quality

  Produce many offspring with little parental care, hoping that at least a few will survive
• Quantity over Quality

  • R-Selected Species
• Quality over Quality

  Invest a lot of energy into caring for a few offspring, ensuring their survival
• Quality over Quality

  • K-Selected Species, Larger organisms
• Survivorship curves

  • Type 1 Survivorship
  • Type 3 Survivorship
  • Type 2 Survivorship
• Survivorship

  The percentage of a given population that's still surviving at any given point in their relative lifespan
• Type 1 Survivorship

  High degree of parental care, almost all offspring survive infancy and make it to adulthood
• Type 1 Survivorship

  • K-Selected Species, Large mammals
• Type 3 Survivorship

  Low degree of parental care, few offspring survive infancy and make it to adulthood
• Type 3 Survivorship

  • R-Selected Species, Smaller organisms
• Type 2 Survivorship

  Consistent mortality rate throughout the relative lifespan of the species
• Type 2 Survivorship

  • Species like small rodents or birds
• Carrying Capacity

  The maximum number of individuals of a given species that an ecosystem can support
• Limiting Factors

  Resources that determine the carrying capacity, such as food, water, shelter, and nutrients
• Density-Dependent Factors

  Factors that limit population growth, and their effects are more pronounced in densely packed populations
• Density-Dependent Factors

  • Competition for resources, disease outbreaks
• Density-Independent Factors

  Factors that impact populations regardless of their density
• Density-Independent Factors

  • Natural disasters, climate change
• Distribution patterns

  • Uniform Distribution
  • Random Distribution
  • Clumped Distribution
• Uniform Distribution

  Equal space between each individual in the population
• Uniform Distribution

  • Seabird populations
• Random Distribution

  Growth depends on chance events, such as seed dispersal and soil conditions
• Random Distribution

  • Tree populations
• Clumped Distribution

  Species that rely on group or herd protection from predators, and tend to stick closely together
• Clumped Distribution

  • Herd animals
• Age structure diagrams

  A form of graph used to visualize the proportion of a country's population that's in each age cohort
• Age cohorts

  • Pre-reproductive age cohort (0-14 years old)
  • Reproductive age cohort (15-44 years old)
  • Post-reproductive age cohort (45 years old and up)
• Total Fertility Rate (TFR)

  The average number of children that a woman in a given population will give birth to in her lifetime
• Countries with high TFR have large pre-reproductive age cohorts
• Factors influencing TFR

  • Average age of first childbirth
  • Economic, social, and cultural factors
• Economic Factors

  In agrarian societies, having more children means more labor and income; limited access to education and family planning resources
• Social and Cultural Factors

  Cultural and religious values may favor having many children; women and families may intentionally choose to have larger families for economic, religious, or cultural reasons
• Education and Economic Opportunities

  Increased access to education and economic opportunities leads to delayed childbirth and decreased TFR; strong inverse relationship between years of education and number of children
• Government Interventions

  Public education campaigns about family planning; economic opportunities for women, such as microcredit loans; mandating lower birth rates, as seen in China