3c Niche

Niche and Climate Envelopes

Overview of Niche and Climate Envelopes

  • Niche and Climate Envelope Concepts:

    • Niche is a critical concept in ecology and evolution.

    • Climate envelope relates to the climate conditions that allow a species to survive and reproduce.

Examples of Species in the Mojave Desert

  • Species Mentioned:

    • Red-tailed hawk

    • Bighorn sheep

    • Desert scorpion

    • Mule deer

    • Antelope ground squirrel

    • Kangaroo rat

    • Kit fox

    • Mountain lion

    • Scott's oriole

    • Coyote

    • Gambel's quail

    • Greater roadrunner

    • Western diamondback rattlesnake

    • Black-tailed jackrabbit

    • Source: www.exploringnature.org

Lesson Objectives

  • Objectives:

    • Define and describe Niche.

    • Define and describe Climate Envelope and Climate Envelope Modeling.

    • Explain predictions by climate scientists about shifts in climate elevation and latitude.

    • Define and describe Dispersal and its importance.

    • Define and describe “assisted migration.”

    • Discuss pros and cons of assisted migration (trade-offs).

Important Concepts

  • Main Concepts Covered:

    • Niche: Key ecological concept. Understanding is crucial for course success.

    • Climate Envelopes: Integral to understanding ecological niches.

    • Climate Change: Impacts on geographical shifts in climate.

    • Dispersal: Movement of organisms.

    • Migration: Refers to ecological migration (gene flow), not seasonal movements.

    • Assisted Migration: Concept and related debate.

    • Reference: Grady et al. paper titled “A Bridge Too Far.”

Defining the Niche

  • Niche (Pronunciation: "nitch" or "neesh")

    • Fundamental concept in ecology and evolution.

    • Two definitions:

    1. Interaction of an organism with its environmental conditions including food, climate, pathogens, competitors, predators, etc.

    2. Sum of adaptations/traits allowing survival and reproduction within its ecosystem.

    • Niche represents how a species interacts and "makes a living" in its ecosystem.

Niche Breadth

  • Niche Breadth:

    • Range of environmental conditions where a species can survive and reproduce, including climate and diet.

Ecological Niche of the Kangaroo Rat

  • Environmental Conditions:

    • Extremely hot summers, freezing winters, minimal groundwater availability.

    • Diet and Movement: Availability of food, competitors (other rodents and quail), and predators.

    • Adaptations:

    • Nocturnal behavior and burrowing for temperature regulation.

    • Ability to drink “metabolic” water through enhanced turbinate bones.

    • Diet consists of seeds.

    • Adaptations for escape: large feet facilitate jumps of up to 9 feet.

Comparison of Other Species' Niches

  • Polar Bear:

    • Environmental conditions to examine: Temperature, water availability, food resources, competitors, and predators.

  • Monarch Butterfly:

    • Environmental conditions to examine: Temperature, water availability, food resources, competitors, and predators.

  • Coronavirus:

    • Environmental conditions to examine: Variables the virus must adapt to, and its adaptations.

Climate Envelope

  • Definition:

    • Part of the niche; defines the climatic conditions allowing a species to survive and reproduce.

  • Geographic Ranges:

    • Climate varies geographically; climate envelopes often spoken about in geographic context (range of species).

    • Example: Saguaro cactus with regards to conditions preventing freezing for 24 hours.

Climate Change and Its Effects

  • Future Predictions:

    • Climate will move up in elevation and shift toward poles.

Example: Saguaro Cactus

  • Behavior in Context of Climate:

    • Range dictated by the inability to survive temperatures freezing for more than 24 hours.

Example: Laurel Sumac

  • Importance in Ecology:

    • Guides citrus grove planting, as its presence marks non-freezing temperatures.

    • Coastal effect impacting temperature variations.

Climate Trends in California

  • Temperature Changes Over Time:

    • Historical Data (1991-2020): Average temperatures in several Californian localities (e.g., Stanford, Tuolumne).

  • Geographic Climate Shifts:

    • Higher temperatures observed in future predictions for current areas like Stanford to be akin to cooler higher altitudes.

Climate Envelope Modeling

  • Description:

    • A climate envelope is part of the niche, indicating environmental ranges conducive to survival.

    • Current species ranges studied alongside geographical patterns.

    • Examples: Studies on Joshua trees and patterns of freezing.

Future Habitat Projections

  • Models Predicting Future Habitats:

    • Focus on geographic ranges adapting to climate forecasts.

    • Importance of migration over these suitable habitats.

Assisted Migration

  • Concept:

    • Moving species to environments where they do not currently exist but will have appropriate climates in the future.

    • Example: Moving Joshua trees from hotter climates to currently cooler areas predicted to warm.

Dispersal Strategies for Plants

  • Methods:

    • Wind: Small seeds carried long distances.

    • Projectile: Plants launching seeds.

    • Animal Dispersal: Through various mechanisms such as ingestion or adherence.

Conservation Biology

  • Definition:

    • Application of ecological principles to address urgent environmental issues (biodiversity loss, habitat destruction, species protection).

Summary Points: Assisted Migration Strategies

  • Assisted Migration Effectiveness:

    • Move species from current to potentially suitable climates, addressing rate of climate change impacts.

Example of Climate Variance Impact on Species

  • Fremont Cottonwood Tree and the significant climate variation observed across ranges.

Research Collection Sites (Grady et al. Study)

  • Elevation Variances:

    • Various collection sites report significant elevation differences impacting ecological studies.