Essential knowledge 1.C.1: Speciation and extinction have occurred throughout the Earth’s history.
a. Speciation rates can vary, especially when adaptive radiation occurs when new habitats become available.
b. Species extinction rates are rapid at times of ecological stress. [See also 4.C.3]
To foster student understanding of this concept, instructors can choose an illustrative example such as:
• Five major extinctions
• Human impact on ecosystems and species extinction rates
✘✘ The names and dates of these extinctions are beyond the scope of this course and the AP Exam.
Learning Objectives:
LO 1.20 The student is able to analyze data related to questions of
speciation and extinction throughout the Earth’s history. [See SP 5.1]
LO 1.21 The student is able to design a plan for collecting data to
investigate the scientific claim that speciation and extinction have
occurred throughout the Earth’s history. [See SP 4.2]
Essential knowledge 1.C.2: Speciation may occur when two populations become reproductively isolated from each other.
a. Speciation results in diversity of life forms. Species can be physically separated by a geographic barrier such as an ocean or a mountain range, or various pre-and post-zygotic mechanisms can
maintain reproductive isolation and prevent gene flow.
b. New species arise from reproductive isolation over time, which
can involve scales of hundreds of thousands or even millions of
years, or speciation can occur rapidly through mechanisms such as
polyploidy in plants.
Learning Objectives:
LO 1.22 The student is able to use data from a real or simulated population(s), based on graphs or models of types of selection, to predict what will happen to the population in the future. [See SP 6.4]
LO 1.23 The student is able to justify the selection of data that address questions related to reproductive isolation and speciation. [See SP 4.1]
LO 1.24 The student is able to describe speciation in an isolated population and connect it to change in gene frequency, change in environment, natural selection and/or genetic drift. [See SP 7.2]
Essential knowledge 1.D.1: There are several hypotheses about the natural origin of life on Earth, each with supporting scientific evidence.
a. Scientific evidence supports the various models.
Evidence of student learning is a demonstrated understanding of each of the following:
1. Primitive Earth provided inorganic precursors from which
organic molecules could have been synthesized due to the
presence of available free energy and the absence of a significant quantity of oxygen.
2. In turn, these molecules served as monomers or building blocks for the formation of more complex molecules, including amino acids and nucleotides. [See also 4.A.1]
3. The joining of these monomers produced polymers with the
ability to replicate, store and transfer information.
4. These complex reaction sets could have occurred in solution (organic soup model) or as reactions on solid reactive surfaces. See also 2.B.1]
5. The RNA World hypothesis proposes that RNA could have been the earliest genetic material.
Learning Objectives:
LO 1.27 The student is able to describe a scientific hypothesis about the origin of life on Earth. [See SP 1.2]
LO 1.28 The student is able to evaluate scientific questions based on hypotheses about the origin of life on Earth. [See SP 3.3]
LO 1.29 The student is able to describe the reasons for revisions
of scientific hypotheses of the origin of life on Earth. [See SP 6.3]
LO 1.30 The student is able to evaluate scientific hypotheses
about the origin of life on Earth. [See SP 6.5]
LO 1.31 The student is able to evaluate the accuracy and
legitimacy of data to answer scientific questions about the origin
of life on Earth. [See SP 4.4]Essential knowledge 1.D.2: Scientific evidence from many different disciplines supports models of the origin of life.
a. Geological evidence provides support for models of the origin of life on Earth.
Evidence of student learning is a demonstrated understanding of each of the following:
1. The Earth formed approximately 4.6 billion years ago (bya), and the environment was too hostile for life until 3.9 bya, while the earliest fossil evidence for life dates to 3.5 bya. Taken together, this evidence provides a plausible range of dates when the origin of life could have occurred.
2. Chemical experiments have shown that it is possible to form complex organic molecules from inorganic molecules in the absence of life.
b. Molecular and genetic evidence from extant and extinct organisms indicates that all organisms on Earth share a common ancestral origin of life.
Evidence of student learning is a demonstrated understanding of each of the following:
1. Scientific evidence includes molecular building blocks that are common to all life forms.
2. Scientific evidence includes a common genetic code.
Tree Thinking case study- have stamped off- correct- turn in after break
FRQ practice- review rubric & score
Tuesday Ch. 26 review + CN
Thursday: Exam: Chapters 22-26
Friday; Chapter reviews 27.1, 27.2/38.1
Monumental events in the history of life presentations due Tuesday BOP
Sign up for 1 of the 21 events- link below (one person per event)
https://docs.google.com/spreadsheet/ccc?key=0Am-FUqbo8gkJdF9zbWVNQThzN19iYnB6RVlKekd5Vnc&usp=sharing
Assignment guidelines and class presentation document
https://docs.google.com/presentation/d/1M35U7Izcr2Voq3Pj9eGsAw01UOUBJny205Zw9u-4byI/edit?usp=sharing