Evolution

Question 1

1700-1900 main scientists and explorers?

Answer 1

Humboldt, Linnaeus, Lamarck and Darwin.

Question 2

Darwinian explanatory core

Answer 2

Natural selection: an important process by which evolution takes place within a population of organisms. Darwin developed four conditions explaining differences between individuals of a same species:

1. Individuals within a population differ. long and short neck giraffes
2. Differences are passed from parents to offsprings.
3. Some individuals are more successful at reproducing and surviving than others. Giraffes with long necks.
4. Successful individuals succeed because of variant traits that they have inherited and will pass onto their offsprings. Giraffes with longer necks are stronger and will pass on this feature to their offsprings.

Question 3

Individual fitness

Answer 3

Biological or Darwinian fitness is defined based on the specimen’s ability to reproduce and generate viable offspring. Essentially, the fitness of the individual is based on its ability to pass genetic information on to the next generation, as opposed to any physical characteristic or trait.

Question 4

Adaptation

Answer 4

Adaptation is a key process through which species change their physical characteristics. These characteristics are passed down to subsequent generations, which also benefit from a biological advantage.

Question 5

The Modern Synthesis

Answer 5

Refers to the early to mid-century formulation of evolutionary theory that reconciled classical Darwinian selection theory with a newer population-oriented view of Mendelian genetics that attempted to explain the origin of biological diversity.

The Darwinian mechanism is spread on a large scale: with a gradual process the population evolves and may transform into a new species.

Geographic barriers as reasons for species differentiation.

Question 6

Speciation

Answer 6

Describes how a new kind of plant or animal species is created. The evolutionary process by which populations evolve to become distinct species.

Question 7

Allopatric speciation

Answer 7

When a species separates into two separate groups which are isolated from one another. A physical barrier, such as a mountain range or a waterway, makes it impossible for them to breed with one another. Each species develops differently based on the demands of their unique habitat or the genetic characteristics of the group that are passed on to offspring.

Question 8

Peripatric speciation

Answer 8

When small groups of individuals break off from the larger group due to physical barriers. The main difference between allopatric speciation and peripatric speciation is that in peripatric speciation, one group is much smaller than the other.

Question 9

Parapatric speciation

Answer 9

a species is spread out over a large geographic area. It is possible for any member of the species to mate with another member, but individuals only mate with those in their own geographic region. Instead of being separated by a physical barrier, the species are separated by differences in the same environment.

Question 10

Sympatric speciation

Answer 10

when there are no physical barriers preventing any members of a species from mating with another, and all members are in close proximity to one another. A new species, perhaps based on a different food source or characteristic, seems to develop spontaneously. The theory is that some individuals become dependent on certain aspects of an environment—such as shelter or food sources—while others do not.

Question 11

Artificial speciation

Answer 11

Made in lab.

Question 12

EES

Answer 12

consists of a set of theoretical concepts argued to be more comprehensive than the earlier modern synthesis. EES states that there is a broader set of causes for diversity of life and processes of adaptation. Inheritance is not just transmission of genes, but also the developmental conditions that parents construct for their offspring.

Question 13

Programmed vs constructive development

Answer 13

Programmed: unfolding according to rules and instructions specified within the genome. Under this perspective, organisms are built from the genome outwards and upwards, with each generation receiving the instruction on how to build a phenotype through the transmission of DNA.

Constructive: causation flows both upwards from lower levels of biological organization, such as DNA, and from higher levels downwards, such as through tissue- and environment-specific gene regulation. Rather than containing a ‘program’, the genome represents a component of the developmental system, shaped by evolution to sense and respond to relevant signals and to provide materials upon which cells can draw.

Question 14

Evolutionary developmental biology

Answer 14

Evo-devo → to consider the development in evolution, not just genetics but also epigenetics. Explores the mechanistic relationships between the processes of individual development and phenotypic change during evolution.

Question 15

Epigenetics

Answer 15

The study of how behaviors and environment can cause changes that affect the way your genes work. Unlike genetic changes, epigenetic changes are reversible and do not change your DNA sequence, but they can change how your body reads a DNA sequence.

Question 16

HET

Answer 16

Emerged since the 1980s at the crossroads of paleobiology, genetics, and developmental biology. Niels Eldredge, paleontologist, argues that evolution integrates both the ecological and the genealogical dimension and that evolution is based on jumps, therefore it is punctuated and not gradual.

Ecological dimension: has to do with matter and energy and their flow; organisms need energy and therefore need matter.

Genealogical dimension: has to do with information, running from the origin until now across time; it is a temporal flow, and it can be represented with the classical tree of life.

These two dimensions are interconnected at the level of the organism, which has a trophic machinery, it needs energy, and it will employ reproductive strategies to transmit its genes to the following generations. Organisms are the subjects interacting in the environment.

Question 17

What is the sixth extinction?

Answer 17

The Big 5
Ordovician-silurian Extinction: 440 million years ago.
Devonian Extinction: 365 million years ago.
Permian-triassic Extinction: 250 million years ago.
Triassic-jurassic Extinction: 210 million years ago.
Cretaceous-tertiary Extinction: 65 Million Years Ago.

Despite these mass extinctions, biodiversity increased. Why? Because extinction = turnover of species. In every crisis the survivors are more diverse and can take on new ways, niches and spaces, gaining the potential to generate new lines of evolution. Despite the crisis, the Earth gets richer in life and more livable → then, humans arrive.

How is the sixth extinction different from past extinctions?

The first extinction that is caused by a biotic factor, rather than physical one → homo sapien, through the:

transformation of landscape
over exploitation of species
pollution
introduction of alien species
Also, the timeframe is much shorter compared to the broader geological times.

Question 18

IUCN

Answer 18

international union for conservation of nature → classifies species according to their extinction rate.

Question 19

Extinction vortex

Answer 19

Extinction vortices are a class of models through which conservation biologists, geneticists and ecologists can understand the dynamics of and categorize extinctions in the context of their causes. This model shows the events that ultimately lead small populations to become increasingly vulnerable as they spiral toward extinction.

Question 20

HIPPO + C

Answer 20

Biodiversity crisis caused by:

H habitat
I invasive species
P pollution
P population growth
O overharvesting
+
C climate change

Question 21

What are the values of biodiversity?

Answer 21

Biodiversity has different values:
Consumptive use value (direct value): food and medicines; Biodiversity loss means that we are lacking the sources of our wellbeing even in this sense.
Indirect use value: non-consumptive use value, multiple use (Ecosystem services, aesthetical, scientific, and recreational values); these are non-material qualities. They include climate regulation and other services that the scientific knowledge from ecology tells us about.
Existence value: intrinsic value → biodiversity exists and therefore it embeds an ethical obligation to be protected.

Question 22

LPI

Answer 22

Living Planet Index is an indicator of the state of global biological diversity, based on trends in vertebrate populations of species from around the world. Exploitation and Habitat loss is the main problem in all countries/continents (change in land and sea use).

Fishes, Amphibians, reptiles, birds, mammals, vertebrates are investigated to calculate their extinction rate, cumulative percentages of extinction. Sharp increase in cumulative extinction happening with the XX century.

Southern America is witnessing the worst extinction rate: -94%. Northern America and Europe+Russia are witnessing a kind of better situation: -33% for North America and -24% for Europe+Russia.

There are skeptical scientists about extinction, but even if some species are not going extinct, the sharp decrease in the number of individuals is an evident sign of degradation.

The LPI was adopted by the Convention of Biological Diversity (CBD) as an indicator of progress towards its 2011-2020 targets and can play an important role in monitoring progress towards the post-2020 goals and targets negotiated at COP15 this December.

Question 23

Main causes of biodiversity degradation?

Answer 23

Changes in land and sea use
species overexploitation
invasive species and disease
pollution
climate chante

Question 24

Convention on Biological Diversity

Answer 24

In 2002 → to achieve a significant reduction in the rate of biodiversity loss by 2010. Most indicators of the state of biodiversity showed declines, with no significant recent reductions in rate, whereas indicators of pressures on biodiversity showed increases. Despite some local successes and increasing responses, the rate of biodiversity loss does not appear to be slowing.

Question 25

Traditional conservationism

Answer 25

Rooted in modern science and ecology: conservation, preservation, restoration. Conservationism has been considered as a western view, it is related to a colonialistic idea of a superior western culture that intervenes just after damaging others’ environments. On the other hand, there is no way to replace real ecosystems with artificial ones. Traditional conservation is still at the basis of the European directive: all of the environmental directives are founded on conservation biology’s concepts. Birds are the only category of animals who has a specific directive: they move a lot of stakeholders, they have a long-range life movement.

Question 26

Human power approach

Answer 26

Tech will solve everything: ecomodernism.

Anthropocene theory: green cities, circular economy, vertical forests, vertical farming. Are we at a stage where tech is the only way forward?

Lovelocks’ Gaia hypothesis - big smart cities and the rest of planet earth can be free to go back to nature…BUT population density is to high for this option.