POPULATION ECOLOGY WHY DO SPECIES LOOK AND BEHAVE

POPULATION ECOLOGY WHY DO SPECIES LOOK AND BEHAVE THE WAY THEY DO?

What is a SPECIES? • ONE TYPE OF ORGANISM • A GROUP OF ORGANISMS WHICH ARE CAPABLE OF BREEDING SUCCESSFUL OFFSPRING

What is a POPULATION? • The number of ONE species in a given area. ex: # of right whales in the North Atlantic ex: # of gray squirrels in Floral Park ex: # of butterfly fish in the fish tank

POPULATION DISTRIBUTION 1. UNIFORM – WHEN THERE IS SEVERE COMPETITION FOR A RESOURCE OR TERRITORIAL DISPUTES ex: desert plants, trees in a forest

POPULATION DISTRIBUTION 2. RANDOM – INDIVIDUALS LIVE INDEPENDENT OF EACH OTHER ex: squirrels in trees dandelion weeds on a lawn

POPULATION DISTRIBUTION 3. CLUMPED – ORGANISMS IN GROUPS DUE TO SOCIAL BEHAVIOR ex: people in cities, herd of elephants, pack of wolves

What is a LIMITING FACTOR? • An environmental condition which controls the size of a population. • • natural disasters predator/prey disease pollution • • birth/death rate climate/weather food/water/shelter birth/death rate

What is CARRYING CAPACITY? • The maximum number of a species that the environment can support. What if the maximum is exceeded? • When carrying capacity is exceed a large percentage of the population dies quickly. This is a POPULATION CRASH

What is an ADAPTATION? • A TRAIT WHICH ALLOWS AN ORGANISM TO SURVIVE. • THESE ARE THOUGHT OF AS “GOOD GENES”.

Moth’s coloring acts like camouflage Frog’s coloring warns predators that it is poisonous Giraffe’s long neck helps it reach leaves Shark’s teeth are sharp to bite prey

WHAT IS A GENE? • A PROTEIN BASED COMPOUND THAT CARRIES OUR GENETIC INFO/TRAITS/CHARACTERISTICS.

WHAT IS A GENE? • GENES ARE FOUND ON OUR CHROMOSOMES IN THE NUCLEUS OF OUR CELLS.

WHAT IS GENE VARIATION? • SMALL DIFFERENCES IN THE GENE POOL DUE TO SEXUAL REPRODUCTION WHICH “MIXES” THE GENES.

WHAT IS A GENE POOL? • THE COLLECTION OF ALL THE GENETIC MATERIAL IN A POPULATION. (ALL THE VARIETIES OF THE GENES)

HOW DO YOU GET GOOD GENES? NATURAL SELECTION OR SURVIVAL OF THE FITTEST • Organisms with “good genes” survive and reproduce. • The “good genes” are passed to their offspring. • The most “fit” organisms survive. • Over time “good genes” increase in frequency, and “bad genes” decrease in frequency.

WHAT IS EVOLUTION? • A GRADUAL CHANGE IN A SPECIES OVER TIME DUE TO CHANGES IN GENETIC MAKEUP. • EVOLUTION TAKES THOUSANDS EVEN MILLIONS OF YEARS.

WHAT IS A MUTATION? • A GENE OR CHROMOSOME IS ALTERED OR CHANGED. • MOST MUTATIONS ARE MINOR AND GO UNNOTICED.

How are genes transferred to offspring? 1. ASEXUAL REPRODUCTION • ONE PARENT • NO CHANGE IN GENES OCCUR • OFFSPRING & PARENT ARE GENETICALLY IDENTICAL

How are genes transferred to offspring? 1. SEXUAL REPRODUCTION • TWO PARENTS (male/female) • VARIATION OF GENETIC MATERIAL • OFFSPRING & PARENT ARE GENETICALLY DIFFERENT

IN SUMMARY: • Species behave and look the way they do because of their genetics. • Species are influenced by their changing environments. • Genes that are “good” today may be “bad” tomorrow.