Adaptation. Adaptation A trait that allows a species to survive more easily and reproduce.

Transcription

1 Adaptation Adaptation A trait that allows a species to survive more easily and reproduce.

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3 Adaptation of Beaks

4 Adaptations of Feet

5 Origin of Life Modern humans (Homo sapiens) appear about 2 seconds before midnight Recorded human history begins 1/4 second before midnight Origin of life ( billion years ago)

6 EVOLUTION Evolution - Inheritance of specific genetic traits that controls adaptations, giving a species an advantage in an environment.

7 Evidence of Evolution Physical Similarities Most animals have similar bones in their limbs (fins, arms, wings) Comparing DNA Vestigial Structures Still exist in the body but are no longer needed Examples...

8 Natural Selection

9 More... Natural Selection

10 Natural Selection Natural Selection - Describes process where better competitors survive and reproduce more successfully. (It is the engine that drives evolution). Caused by: Random mutations Changes in DNA are usually bad, but can be beneficial. Selective pressure Limited resources mean only the best competitors survive. Sexual selection Females choose a mate based on certain characteristics.

11 Factors Exerting Selective Pressure Physiological stress due to inappropriate levels of a critical environmental factor. Moisture, Light, ph Predation Organism is hunted and killed by another Includes parasites, bacteria, viruses Competition Other organisms attempting to use same resources Luck

12 Artificial Selection The selective breeding of organisms by humans for specific characteristics.

13 Speciation Given enough time, enough mutations occur that a new species develops from an old one. When are two groups considered a different species? - They cannot (or will not) interbreed to produce healthy, fertile offspring. - The original population of these squirrels was separated by formation of Grand Canyon. Now if brought together they cannot breed.

14 Types of Speciation Divergent - Separation of one species into new species.

15 Types of Speciation Convergent - Unrelated organisms evolve to look and act alike. Not related Caused by living in similar environments

16 Coevolution The process of two species evolving in response to long-term interactions with each other.

17 Same or Different Species?

18 Animal Hybrids or New Species? More examples jaguar/lion zebra/donkey domestic canary/goldfinch

19 Crayfish The Taxonomic Naming System a.k.a. Crawdad a.k.a. Spiny lobster a.k.a. Yabby a.k.a. Crawfish a.k.a. Creekcrab a.k.a. Mudbug We need an internationally accepted name!

20 Scientific Naming System Based on the classification system. Includes the organism s genus and species name. Genus is capitalized Species is lower case The scientific name is written in italics Scientific name of the crayfish: Procambarus clarkii

21 The Taxonomic Naming System Divides organisms into different levels of organization. Kingdom Phylum Class Order Family Genus Species The more levels two organisms have in common, the more related.

22 Know YOUR Classification

23 How related are they? For years the domestic dog was classified as a species (Canis familiars). However, DNA analysis revealed domestic dogs evolved from wolves. This led scientists to reclassify dogs as a subspecies of the wolf rather than a separate species. Canis lupus European Wolf Canis lupus familiaris Domesticated dog

24 How related are they? Chlorurus microrhinos parrot fish Ara ararauna parrot (blue and yellow macaw)

25 Phylogenetic Tree Also known as a tree of life. Organisms are grouped and classified based on three characteristics: Physical characteristics DNA Behavioural characteristics - Mating rituals, territorial, aggression, etc. The more of these characteristics two organisms have in common, the more closely related they are according to evolution.

26 Phylogenetic Tree of Life From left to right: 1. Orangutan 2. Gorilla 3. Human 4. Chimpanzee 5. Bonobo