Mutation, Variation & Adaptation By Dr π Rat

A change in the base sequence in DNA Mutations A change in the base sequence in DNA Can occur randomly (naturally) Or can be deliberately caused in the laboratory by scientists or by mutagens in the environment Inherited if occur in the gametes Not always harmful http://www.accessexcellence.org/

Mutation during Mitosis Only affects new body cells. The mutation cannot be passed on to the affected individual’s offspring. Examples: Individual with two differently coloured eyes Skin cancer as a consequence of UV damage

Mutation during Meiosis Mutation occurs during the formation of gametes (eggs, sperm, pollen). The zygote will be mutated if a mutated gamete is creating it. Every subsequent cell of the new organism will be mutated (mitosis). The mutation will be passed on to the next generation (inheritable mutation).

Natural Mutations: ALBINOS Little or no pigmentation in the eyes, skin, and hair (or in some cases in the eyes alone). Inherited an altered copy of a gene that does not work correctly. The altered gene does not allow the body to make the usual amounts of a pigment called "melanin". True albinos have pink eyes and skin.

Albinos

These are not albinos; they have pigmented eyes.

White Bengal Tiger

Variations Either/or or discrete variation – you either have it or you don’t; usually produced by a single gene with a dominant or recessive allele (expressed as a % of the population). E.g. tongue rolling Continuous variation - (expressed as a bell shaped curve) E.g. hand span, size, shoe size, colouring Non-inheritable variations

Non-inheritable Variation Variation resulting from the organism’s lifestyle or environment are called non-inheritable. Example: Neptune’s Necklace seaweed in high wave action areas  small beads in calmer water  bigger beads

Variation of Phenotype triggered by temperature – Non-inheritable Variation Tuatara eggs are turning out as follows: cold temperature  females warm temperature  males

Variation of Phenotype triggered by pH – Non-inheritable Variation Hydrangeas change their colour with the pH of the soil: Alkaline soil makes them go red Neutral and acidic soil makes them go blue

Variation of Phenotype triggered by Light – Non-inheritable Variation Leaf size of trees changing with the light intensity (and wind exposure)

Variation of Phenotype triggered by Wind – Non-inheritable Variation

Variation of Phenotype triggered by Wind – Non-inheritable Variation

Phenotype Genotype + Environment  Phenotype Phenotype = how the organism looks is dependent on the genotype plus non-inheritable (environmental) effects.

Mutation is the Mother of Evolution Mutation is the source of all variation Variation gives an opportunity for adaptation: If the varied new organism has an advantage relative to its non-mutated siblings, it will be more successful to survive and it will adapt better to its environment. E.g. Antibiotic-resistant bacteria Pesticide resistant bugs

Adaptations Organisms need to have special features which help them to survive in their habitat. These special features are called ADAPTATIONS. For example: You have plenty of adaptations to survive in your habitat. Your fingers are an excellent adaptation. Without their ability to grip you would not be able to do all of that schoolwork! Can you think of other adaptations that you have?

Types of Adaptations Anything that helps an organism survive better in its environment is an adaptation.  There are three basic types of adaptations Structural adaptations (how something is built) Behavioural adaptations (what an organism does) Physiological adaptations (what happens inside an organism, its bio-chemistry)

Structural Adaptations are design features in the organism (plant or animal) that help it to survive better in its habitat. Examples A bird has wings to fly An elephant has a trunk to grab food A Kiwi has a long beak to probe for worms Alpine plants grow close to the ground You have two feet for upright walking Worms are long and thin

Behavioural Adaptations are learned actions or “innate” actions (a behaviour an animal is born with) or movements that make an organism survive better. Examples A chicken scratches the ground to find worms for food A stick insect stops moving when it sees a predator bird A hedgehog rolls itself into a ball when attacked by a dog A plant turns its leaves towards the sun Small fish swim as a school

Physiological adaptations Are biochemical features of an organism that help it to survive better in its habitat. Examples You are warm-blooded so that you can move faster in spite of very cold temperatures. Tropical fish require temperatures of 25°C or higher in order to have their digestive enzymes work (they starve to death in cold water despite having plenty of food) Dogs can digest meat but not cellulose (cell walls of plants) Sheep can digest cellulose but not meat

What type of Adaptations are the following? Mimicry Hibernation

What type of Adaptations are the following? Migration Camouflage

Table of Adaptations: Name of organism Feature Type of adaptation Function Reason Rabbit big ears structural better hearing to escape predators behavioural physiological

List Adaptations for the following totara Totara tree

List Adaptations for the following piwakawaka Fantail

List Adaptations for the following aihe Hector’s Dolphin

List Adaptations for the following kōtare NZ Kingfisher

List Adaptations for the following katipo Katipo Spider

Human Intervention

Selective Breeding The selection of certain seeds or animals for reproduction in order to influence the traits inherited by the next generation.

Selective Breeding in Farming We select desirable traits in plants and animals we work with. We do not breed from weak or undesirable organisms. Over decades of “selective breeding” the genetics of our “domesticated” animals and plants has changed from “wild” organisms. The feral traits have been bred out of the stock or cultured plants.

SELECTIVE BREEDING The Liger is the result of breeding a female Tiger to a male Lion. The liger has both stripes and spots. The stripes are inherited from its tiger parent and the spots from the lion parent. On their hind legs, ligers stand approximately 12 feet tall. At most, ligers may weigh up to 1,000 pounds.

The Cama is the result of breeding a Llama to a Camel The Cama is the result of breeding a Llama to a Camel. Parents in background of picture.

The Zebroid is the result of breeding a female Horse and a male Zebra. The Zedonk / Zonkey is the result of breeding a female Donkey and male Zebra.

The Mule is the result of breeding a female horse (mare) to a male donkey (jack). The mule is superior to the horse in strength, endurance, intelligence and disease resistance.

The selective, deliberate change of genes (genetic material) by man. Genetic Engineering The selective, deliberate change of genes (genetic material) by man. The technique of removing, modifying or adding genes to a DNA molecule in order to change the information it contains.

                                                                                                                    French genetic researchers created Alba for artist Eduardo Kac. Thanks to genes borrowed from a jellyfish, the albino rabbit glows green when placed under special lighting. In regular light, Alba appears like any other furry white rabbit. But place her under a black light, and her eyes, whiskers and fur glow a otherworldly green.

                                                                                                                                                       "Glow in the dark" fish. these genetically modified fish were developed by a Taiwanese aquatic firm, Taikong Group. They are planning to reproduce these fish in numbers and sell them for pets.

                                                                                                                                    Scientists in the agriculture department of the Hebrew University in Rehovot have genetically engineered a chicken that has no feathers.