Biology - Evolution

Charles Darwin

Charles Darwin

Scientist, naturalist, and author of "On the Origin of Species"

HMS Beagle

Name of the ship Darwin sailed on for five years

What are three things Charles Darwin collect?

fossils, plants, animals

Galapagos Islands

Isabela Island (Dome-shaped turtle), Hood Island (Saddleback turtle), and Pinta Island (Intermediate Turtle). (Darwin noted that the tortoises' traits varied from island to island due to their different habitats)

The HMS Beagle's voyage length of time

5 years

Artificial selection

breeding process done by humans for a desirable trait outcome, typically to enhance a certain feature (ex

Natural selection

the process through which species adapt to their environments, the reason for evolution; affects PHENOTYPE (PHYSICAL TRAITS), not genotype (genetic makeup).

Four steps of natural selection

Overproduction, Variation, Competition, and Selection.

Evolution

the passing of traits over time/ slight gradual changes.

The origin of species by means of natural selection (What was the book about?)

The book was about how evolution takes place through a process called natural selection. Natural selection is the process by which organisms better suited for adaption to their environment survive, while those that are poorly suited to their environment do not.

Fossil

a record of the history of life on Earth

Types of rocks

sedimentary (formed by pre-existing rocks or other organisms); igneous (hot, molten rock solidifies); metamorphic (started out as some other type of rock like sedimentary and igneous rock but changed due to extreme heat and pressure).

Pangea

landmass that consisted of all the continents on Earth; all continents were connected

Plate tectonics

a theory explaining the structure of the earth's crust and many associated phenomena resulting from the interaction of rigid lithospheric plates which move slowly over the underlying mantle.

Geological Time Scale

a representation of time passed based on the rock record of Earth (can be done by carbon dating, etc.)

Law of superposition

law stating that the bottom layer is the oldest, and the top layer is the youngest, or newest (ONLY IN SEDIMENTARY ROCKS)

Embryo

an unborn or unhatched offspring in the process of development, in particular, a human offspring during the period from approximately the second to the eighth week after fertilization (after which it is usually termed a fetus).

Embryology

the study of embryos → shows that all embryos look similar before developing species-specific traits

Fitness

the ability to survive long enough to reproduce

Adaptation

an inherited trait that increases an organism's chances of survival

Mimicry

the ability for an organism to look and act like another organism, one being potentially harmful or poisonous, for survival

Variation is important because an environment with more species has a better chance of survival, however, an environment without variation has a lower chance of survival. (Ex. - An environment with only Bears and Mice is not sufficient, and without food, the bear and mice will eventually die off.)

Why is variation important?

Descent with modification

each living species has descended, with changes, from other species over time

Common descent

all living organisms are related to one another

Cladogram

a diagram that depicts evolutionary relationships among groups of organisms.

Cladistics

a form of analysis that looks at features of organisms that appear within new species that the previous did not have that serve a certain purpose.

Fossil record

a record history of life on earth by fossils

Homologous body structures

similar anatomy in different types of animals because of a common ancestor (ex

Analogous Structures

used for the same purpose and can be superficially similar in constriction, but are not inherited from a common ancestor; show that functionally similar features can evolve independently in similar environments (ex

Vestigial structures

"leftover" traces of evolution that serve no purpose (ex

Embryology

the study of embryos → shows that all embryos look similar before developing species-specific traits

Biochemical Evidence

DNA with more similar sequences suggest species are more closely related

James Hutton

Geologist whose work lead to the theory that the earth was older than 6,000 years old

Charles Lyell

Worked with Hutton to produce a theory that the earth is extremely old and the same processes that operated in the past, operate in the present

Jean-Baptiste Lamarck

proposed that organisms had an inborn urge to become complex and perfect, and could change during their lifetimes by selectively using or not using various body parts (These new changes and features would help the organism survive; Also suggested that individuals could pass these acquired traits on to their offspring, enabling species to change (evolve) over time)

Thomas Malthus

noted that overcrowding was occurring because the rate of birth was high than the rate of death (in humans); Suggested forces that work AGAINST population growth are war, famine, and disease; if the human population when unchecked, there wouldn't be sufficient living space or food for everyone