Scientists classify plants to understand and identify the relationships between all the different species of organisms and to sort them into groups by using various systems of classification. Scientists name different species of plants to describe both the genus and the species of plants to be able to categorize them, a system that has been used throughout the years is the binomial, the binomial is a two-name system of nomenclature was created by a well-known naturalist Carl Linnaeus in the 1700s, since then scientists name the plants according to Linnaeus binomial naming system. Taxomic is where biologists are concerned with the classification of things, organisms especially. Species is a group of organisms that share similar characteristics that are capable of exchanging genes or interbreeding.
Jean baptize lamarch’s theory in the 1800’s “evolution is the inheritance of acquired characteristics.” (anon,2018) although a better theory came from a naturalist named Charles Darwin, Darwin had studied animals in the 19th century. he proposed his theory in 1858 of evolution and natural selection where animals adapt to their environment over many years and evolve to survive better in their environment. The first bit of his theory involves ” indivials that poorly adapted to their environment are less likely to survive an reproduce”(action,W,garden,P,2017) this most likely means that their genes would have a hard time being passed to the next generation, but over a couple of years the species will evolve and adapt better to the climates and their surroundings of the environment, this can also affect the heritable physical or behavioral traits. Darwin’s theory is described by ‘survival of the fittest’ that’s not always correct it’s not about how fit an animal or plant is it more about how they have adapted to their environment and how they reproduce to survive. The Continental drift one of the most well-known theory’s, in the 20th century a man named Alfred Wegener came up with a theory of the continental drift, his idea was about how the earth’s continents many millions of years ago were once all joined together but they slowly moved apart over the years. This theory offered an answer to the existence of different fossils of the remains of an organism that may have existed in the past that had similar characteristics as well as the rocks on certain continents that are many kilometers away from each other.
However, this theory was not accepted by other scientists for many years. Before Wegener came up with this idea, it was believed that maintains were formed due to the earth’s climate decreasing getting colder, this was also what was believed to cause the wrinkles or mountains in the earth’s crust, but this is not correct because if it was mountains would evenly be forming over the earth’s surface. This is when Wegener suggested the mountains formed when a continent collided with another somehow managing to reform the land folding and shaping it, an example of this is when India collided with Asia this caused the Himalayas to form. The evidence that Wegener used to create his theory of the continental drift was that the fossilized animals/ plants were not only found in south America but in Africa as well, the east coast of south America and the west coast of Africa shapes fit very well together like two pieces of a puzzle, and finally rock formations and mountains were found in south America and Africa that were matching.
Geologists believed that once there were land bridges in between the continents allowing many animals and plant growth to go between the different continents, but not everything made sense to this explanation because there was no explanation on how the continents moved away from each other but in the 1950s there was evidence that showed the ocean floor spreading by only a few centimeters each year that explained the movement of different parts of the earth’s crust which is now known as the tectonic plates. tectonic plates are the earth’s crust and the upper mantle, they fit together just like puzzle pieces each with certain shapes that fit together, the mantle below is solid but it does move although this movement is a long slow process which explains how the continents moved away from each other over the millions of years. Ocean floor spreading occurs when the tectonic plates in the mid- ocean ridges move apart, the molten material known as magma from deep inside the earth’s crust slowly discharges from it and hardens into a solid this process is what we call “sea floor spreading”. The hardened magma is not just any origanary rock it points in the direction of the magnetic field, this field changes over time and it may even reverse, the changes are all in the way the hardened magma records, scientists can now see the magnetic patterns on all sides of the ocean ridges.
Australia is known to hold the most species of Acacia; the acacia plant is from the mimosaceae family as well as the largest genus of vascular plants. Acacias can be found in many different biomes such as savanna, tropical, desert but acacias mostly thrive in coastal, sub alpine either with high or low rainfall. Majority of acacias flower during spring and summer, they have a decrease in flowering in autumn and winter as the climate has changed to a much colder temperature. The banksia can only be found in Australia. Banksia’s thrive in the east coast of Australia, apparently there is 172 banksia species known to be in Australia as well as 60 species to be in the southwest of Australia.
The banksia has 4 subspecies that are starting to separate out. Natural selection consists of two types of evolution the microevolution and macroevolution. The acacia and banksia species have undergone macroevolution through adaptions once the Pangea and Gondwana parted. This is shown when the different banksia and acacia species in the herbarium are compared, as a few have similar characteristics while others have adapted to make a new species altogether.
Australian acacias and banksias evolved due to the long isolation that Australia has undergone from other continents. In the Cretaceous period, flora began to localize due to the separation of the Pangea, a great flood Pangea was once again separated into four islands. By the separation of Pangea, the divergent evolution had occurred within the acacias and banksia’s. divergent evolution is a common process due to the organisms begin with traits similar to each other which evolve into dissimilar species. this is shown when certain banksias such as the spinulosa and longifolia as they have developed serration in its leaves it has not adapted to survive in tropical biomes.
