Every organism has a niche; the organism’s habitat, its tolerance limits and its function within that habit.

• Define a niche. 

• State factors that restrict the niche of a species.

• Distinguish between the fundamental and realized niche. 

• Compare niche generalists and specialists. 

Not currently taught: 

(SHS does not teach option C)

• Use a transect to correlate the distribution of a species with an abiotic variable.  

• Explain why two species cannot survive indefinitely in the same habitat if their niches are identical.

• State that organisms that can adapt to extreme niches encounter less competition and predation.

The distribution of species is affected by limiting factors (C.1.U1).

Each species plays a unique role within a community because of the unique combination of its spatial habitat and interactions with other species (C.1.U3).

Two species cannot survive indefinitely in the same habitat if their niches are identical (C.1.U5).

Application: Distribution of one animal and one plant species to illustrate limits of tolerance and zones of stress (C.1.A1).

Skill: Analysis of a data set that illustrates the distinction between fundamental and realized niche (C.1.S1).

Initial Knowledge Audit (ICI)

• For students

• For teachers

Niche notes (ICTD)

Niches Check In (OCI)

• For teachers

• For students

Species have adapted through natural selection to fill available niches.

• Define adaptation. 

• Explain how natural selection can lead to adaptations to niches.

• Outline the physiological, morphological and/or behavioral adaptations of Emperor penguins. 

• Outline the physiological, morphological and/or behavioral adaptations of Marram grass.

Bird adaptations activity (ICG) 

Adaptations Padlet (ICTG)

• Marram adaptations 

Evolution of homologous structures by divergent evolution explains similarities in structure when there are differences in function.

• Define homologous.

• Outline examples of different types of homologies. 

• Define divergent evolution. 

• Describe how divergent evolution explains the pattern found in vertebrate limb structure yet allows for the specialization of different limb functions. 

Examples of homologous structures include the pentadactyl limb and the modification of leaves and flowers.

• Define pentadactyl limb.

• List the bone structures present in the pentadactyl limb.

• Identify pentadactyl limb structures in diagrams of amphibians, reptiles, birds and mammals.

• Relate differences in pentadactyl limb structures to differences in limb function. 

• Describe the structure of a typical leaf.

• Explain how traps, spines, tendrils and bulbs are homologous.  

• List the structures and functions of a typical flower. 

• Explain how flowers from different species are homologous. 

   

Evolution of homologous structures by adaptive radiation explains similarities in structure when there are differences in function (5.1.U4)

Comparison of the pentadactyl limb of mammals, birds, amphibians, and reptiles with different methods of locomotion (5.1.A2)

Looking for patterns, trends and discrepancies- there are common features in the bone structure of vertebrate limbs despite their varied use (5.1.NOS).

Homologous structures notes (ICTD)

Skeleton comparison lab (PSOW) 

Pentadactyl Limb Notes (ICTD)

Pentadactly limb photo labeling task (PSOW)

Artist Analyzes Animal Anatomy By Comparing It To Humans In 14 Interesting Illustrations 

Leaf and FLower Homologies Notes (ICTD)

Flower dissection (PSOW)

Flowers Watercolors (PSOW)

The fossil record provides evidence of divergent evolution. 

• Outline how fossils provide evidence of divergent evolution.  

• Use an example from the fossil record to illustrate evolution of an organism.

Fossils notes (ICTD)

These notes have information about types of fossils and absolute dating that is beyond the scope of the IB curriculum.  However, since these topics used to be part of the curriculum, they are still in the slides.  It’s available for students to view, but not assessed. 

HHMI Earth Viewer (ICI)

• Updated link for the interactive website

Fossil Fondu activity (ICI)

Whales case study (ICTD)

A&B:  the evolution of whales from land to sea

Modeling Half Life (PSOW)

A Date with Carbon (A&B)

Taking Wing (A&B)

Step by step evolution (A&B)

It’s a Fishapod (A&B)

• For students

• For teachers

When a change in the environment opens new environmental niches, organisms diversify rapidly from an ancestral species into a multitude of new forms.

• Define adaptive radiation.

• Outline an example of adaptive radiation.

Adaptive Radiation Notes (OCI)

With dinosaurs out of the way, mammals had a chance to thrive  (A&B)

Adaptive radiation of snakes (A&B)

Review of divergent evolution (ICTD)

Adaptation under a microscope (A&B)

Gradualism and punctuated equilibrium are two ways in which the evolution of a species can occur.

• Define gradualism.

• Define punctuated equilibrium.

• Identify gradualism and punctuated equilibrium  from graphs of morphology changes over time.

• Outline a possible cause of rapid evolutionary change events.

Speciation due to divergence of isolated populations can be gradual. (10.3.U4)

Speciation can occur abruptly (10.3.U5)

Pace of Evolution notes (ICTD)

TOK:  punctuated equilibrium was long considered an alternative theory of evolution and a challenge to the long established paradigm of Darwinian gradualism.  How do paradigm shifts proceed in science and what factors are involved in their success? 

Pace of Evolution in Fictional Fossils (PSOW)  

• Original lesson source (with “fossils” to cut out)

• Picture of timeline results

Analogous structures evolve by convergent evolution to fulfil the same function. 

• Define analogous.

• Outline how convergent evolution results in analogous structures.

• Outline a plant and animal example of analogous structures.

Analogous structures notes (OCI)

Homologous analogous challenge

• Submission form for students

• Submission form for teachers

Kahoot review (ICTD)

Quizizz Review (OCI)

1 page-summary (OCI)