A)
On the voyage of the Beagle (1831-1836)
the fossils in South America are dissimilar to European fossils but have similarities with extant (i.e. currently living) plants and animals in South America.
In the hierarchial classificatory system of Linnaeus there is a tacit acknowledgement of relatedness, for example, species belonging to one genus have more in common with each other than they do with species belonging to another genus.
Cuvier believed that the discontinuities between fossils in different strata were brought about by catastrophes such as floods which caused the extinction of many species living at a particular time. This interpretation of earth's history is termed catastrophism and was also held by many contemporary geologists.
Hutton and subsequently Lyell held that geological processes are slow and subtle but that over prolonged periods of time (millions of years) these can lead to major changes
implicit in this viewpoint is an age for the earth radically different from the 6,000 years of the biblical creationists.
"descent with modification"
In assessing the contribution of Darwin and Wallace it should be noted that the key role in heredity of the nucleus, chromosomes and DNA were not demonstrated until 1892, 1903, 1943
For example, in the case of human phylogeny both skeletal structure (comparative morphology) and gene structure (molecular biology) indicate that humans are more closely related to chimpanzees than to New World monkeys.
People who have a general interest in science are likely to dismiss evolution as a soft science after absorbing the pop science nonsense that abounds. The impression of it being a soft science is reinforced when biologists in unrelated fields speculate publicly about evolution.
evolution: a change in the gene pool
The frequency of the dark morph increased in the years following. By 1898, the 95% of the moths in Manchester and other highly industrialized areas were of the dark type.
Evolution can be divided into microevolution and macroevolution. The kind of evolution documented above is microevolution. Larger changes, such as when a new species is formed, are called macroevolution. Some biologists feel the mechanisms of macroevolution are different from those of microevolutionary change. Others think the distinction between the two is arbitrary -- macroevolution is cumulative microevolution
They do not necessarily become better in any absolute sense over time. A trait or strategy that is successful at one time may be unsuccessful at another
At 45 percent of loci in plants there is more than one allele in the gene pool. [allele: alternate version of a gene (created by mutation)] Any given plant is likely to be heterozygous at about 15 percent of its loci
Some types of organisms within a population leave more offspring than others. Over time, the frequency of the more prolific type will increase. The difference in reproductive capability is called natural selection. Natural selection is the only mechanism of adaptive evolution; it is defined as differential reproductive success of pre- existing classes of genetic variants in the gene pool.
Biologists have found that these bats form bonds with partners and help each other out when the other is needy. If a bat is found to be a "cheater," (he accepts blood when starving, but does not donate when his partner is) his partner will abandon him. The bats are thus not helping each other altruistically; they form pacts that are mutually beneficial.
Malthus was a political economist who was concerned about, what he saw as, the decline of living conditions in nineteenth century England. He blamed this decline on three elements: The overproduction of young; the inability of resources to keep up with the rising human population; and the irresponsibility of the lower classes. To combat this, Malthus suggested the family size of the lower class ought to be regulated such that poor families do not produce more children than they can support. Does this sound familiar? China has implemented a policy of one child per family (though this applies to all families, just those of the lower class).
He is best known for his famous debate in June 1860, at the British Association meeting at Oxford. His opponent, Archbishop Samuel Wilberforce, was not-so-affectionately known as "Soapy Sam" for his renowned slipperiness in debate. Wilberforce was coached against Huxley by Richard Owen. During the debate, Archbishop Wilberforce ridiculed evolution and asked Huxley whether he was descended from an ape on his grandmother's side or his grandfather's. Accounts vary as to exactly what happened next, but according to one telling of the story, Huxley muttered "The Lord hath delivered him into my hands," and then rose to give a brilliant defense of Darwin's theory, concluding with the rejoinder, "I would rather be the offspring of two apes than be a man and afraid to face the truth." Huxley's own retelling of the tale was a little different, and quite a bit less dramatic
Wegener found that large-scale geological features on separated continents often matched very closely when the continents were brought together. For example, the Appalachian mountains of eastern North America matched with the Scottish Highlands, and the distinctive rock strata of the Karroo system of South Africa were identical to those of the Santa Catarina system in Brazil. Wegener also found that the fossils found in a certain place often indicated a climate utterly different from the climate of today: for example, fossils of tropical plants, such as ferns and cycads, are found today on the Arctic island of Spitsbergen. All of these facts supported Wegener's theory of "continental drift." In 1915 the first edition of The Origin of Continents and Oceans, a book outlining Wegener's theory, was published; expanded editions were published in 1920, 1922, and 1929. About 300 million years ago, claimed Wegener, the continents had formed a single mass, called Pangaea (from the Greek for "all the Earth"). Pangaea had rifted, or split, and its pieces had been moving away from each other ever since. Wegener was not the first to suggest that the continents had once been connected, but he was the first to present extensive evidence from several fields.
Geoffroy spent much time drawing up rules for deciding when structures in two different organisms were variants of the same type -- in modern terminology, when they were homologous. His criterion was connections between parts: structures in different organisms were the same if their parts were connected to each other in the same pattern. As Charles Darwin described his work in 1859
over 50 islands
In 1535, a Spanish captain, Thomas de Berlanga rediscovered the Galapagos archipelago.
The Baltra airport was originally constructed by the U.S. military during World War II as a base to protect the Panama Canal from enemy attack. During this period most of the indigenous fauna of the island was exterminated.
this mating is in preparation for laying 2-3 years later
Ecology Native to or confined to a certain region.
pahoehoe (a Hawaiian term) or ropey lava,
White-tipped Reef Sharks are fairly innocuous and usually won't bother you unless you bother them.
Palo Santo means holy stick as the aromatic twigs are used for incense in some religious ceremonies in Ecuador
gular sack E)
SEDIMENTARY ROCK
METAMORPHIC ROCK
The fossilized bones of the horse, hidden for millions of years, are exposed above the ground.
Goats & Sheep , Horses, pigs , Rhinos
Hoofed animals with an even number of toes are called artIodactyls
Rhinos and Horses
North America until about 5 million years ago
Today tapirs live only in Malaysia and parts of Central and South America.
They can move faster
Kalobatippus
This horse has reallly long legs , Fossils of this horses are found in the western US , They live from 24 - 19 million years ago.
Dinohippus
This horses fossils are found in the Upper Miocene of North America and date from 13 - 5 million years ago. Ancestor of this horse is Equus .
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