Species Diversity: Biodiversity

SBI3U (Secours) ~ Hyperdoc #1 + cladograms

Biodiversity

the natural diversity or variation of living organisms

Sustainable Development

development that meets the needs of the present without compromising the ability of future generations to meet their own

3 main levels of biodiversity

1. Specific Diversity

2. Genetic Diversity

3. Ecosystem Diversity

Specific Diversity

variety that exists in the different species found in a given area

Genetic Diversity

variety that exists at the level of alleles, entire genes, or chromosomal structure within species

Ecosystem Diversity

variety that exists in physical environments and biotic communities in an ecosystem

Around ______ species are discovered every year

10 000

Ecoservices

the benefits that sustainable ecosystems provide to the organisms that live in them are linked to ecosystem diversity

ex: pollination, pest control, waste management

Anthropocene

term that describes a geological period during which humans caused the majority of planetary changes

⇨ believed to be the next great extinction

LUCA

“Last universal common ancestor”, the original unicellular ancestor that all living things evolved from

Macroevolution

large-scale evolution that can lead to the appearance of new species

3 domains of life

1. Eubacteria

2. Archaea

3. Eukarya

Species biodiversity

• Biodiversity is linked to the # of species on Earth

• more unique species = less competition

• individuals adapt to specific ecological niches

Why is biodiversity in danger?

climate change and human impacts on the environment such as noise and pollution

Why is it difficult to accurately describe a species?

☆ Individuals of different species can be very similar

ex: DNA of orcas shows that they are 3 distinct species

☆ Individuals of the same species can be variable

ex: male vs female, or different stages of life

Phylogeny

the history of the evolution of a species and their relationships

Why is phylogeny useful?

It helps determine common ancestors, or which organisms are most related to each other

Phylogenetic System

classifies organisms on the basis of ancestral relations

Phenetic System

classifies organisms on the basis of morphological similarity (form/shape)

Name the type of system of classification

phylogenetic

Name the type of system of classification

phenetic system

Taxonomy

a branch of biology which aims to identify, name, and classify species according to their natural characteristics

Carl Linnaeus

• the father of taxonomy

• created the first classification system

• grouped organisms based on homologous characteristics (similarities from common ancestors)

• grouped species into levels, called taxa

Taxa

a group that refers to organisms

⇨ ex: the order Rodents, or the phylum Chordata

The 8 taxa

1. Domain

2. Kingdom

3. Phylum

4. Class

5. Order

6. Family

7. Genus

8. Species

🐆 Example of the 8 taxa: LEOPARD (Panthera pardus)

D: Eukarya

K: Animalia

P: Chordata

C: Mammalia

O: Carnivora

F: Felidae

G: Panthera

S: Pardus

The 6 kingdoms of life

1. Animals (Animalia)

2. Plants (Plantae)

3. Fungi

4. Protists (Protista)

5. Archaea

6. Bacteria (Eubacteria)

Binomial Nomenclature

A system of naming plants & animals where each species is given an italicized name consisting of 2 terms:

1. genus (capitalized)

2. species

Biological names show relationships, so species with the _____ genus name are _____ related

same, closely

Dichotomous Key

an identification tool which consists of a series of binary choices which guide towards the identification of organisms

Autotroph vs Heterotroph

An autotroph is an organism that produces its own food, while a hetertroph consumes other organisms

Why doesn’t the Protista kingdom represent a phylogenic group?

they are a paraphyletic group, meaning they exclude certain eukaryotic organisms that share a common ancestor with them, and are spread across several eukaryotic supergroups. 

Cladistics

classification based on common ancestry

Cladograms

diagrams that are constructed using morphological evidence, classification based on derived traits

• species are placed in order that they descended from common ancestor

☆ a type of phylogenetic tree

Derived trait

a characteristic that evolved within one group but not another

☆ represented on a cladogram as hash marks or dots

Closely related species share more ______ _____

derived traits

Ancestral/Primitive trait

a characteristic that evolved in a common ancestor

Clade

a group of species that shares a common ancestor

☆ will form a triangle shape on the cladogram

Why are cladograms useful?

by looking at the shared, derived characteristics, we can use them to infer evolutionary relationships

At each branch point lies the ____ ______ common ancestor of all the groups descended from that branch point

most recent

The y-axis of a cladogram represents ____

time

If one species’ line is ______ than the rest on a cladogram, that species is _____

shorter, extinct

when looking at an organism on a cladogram, the organisms to the ____ of it are more related to it than the ones on the _____

right, left

when looking at an organism on a cladogram, all organisms to the ____ of it are ____ as related to it

right, equally

🐸 provide an example of an adaptation that has made a particular species successful (multiple possible answers)

Tree frogs secrete a wax so they can stay in direct sunshine, unlike other frogs