Fossils and Fossilization - Class X

The Biogenetic Law, proposed by Ernst Haeckel, is synonymous with the Recapitulation Theory, which states that ontogeny recapitulates phylogeny.

Australopithecus fossils found in East Africa (Ethiopia/Tanzania) are known for being bipedal (walking upright) and relatively short, fitting the description provided.

Statement (iii) is incorrect because casts are impressions, not fossilized prints in mud. Statement (iv) is incorrect because fossils in lower strata are generally older than those in upper strata, not the other way around.

Archaeopteryx is considered a transitional fossil (a link between reptiles and birds), not a living fossil. Living fossils are extant organisms that resemble ancient ancestors, such as the platypus or lungfish.

If the fossil of an organism is found in the deeper layers of Earth then it can be predicted that the extinction of organism has occurred thousand years ago.

The dead and decomposing matter in the soil gets suppressed in the lower strata of the soil which turn into fossils due to pressure and temperature in the lower strata of the earth crust. Age of fossils can be detected by the quantity of radioactive carbon compound. Radiocarbon dating is used for determining the age of an object containing organic material by using the properties of radiocarbon (14C), a radioactive isotope of carbon. 

Fossils are organic products which are conserved in the Earth's crust. This means that the fossil is usually formed on or under the Earth's surface or under the water. In other words in the biosphere (think about the biosphere limits). Then this organic material is covered by debris and etc. and becomes the fossil material. The sedimentary rocks are the one type which can contain fossils because these rocks are formed on the Earth surface, under the water etc. In other words, the biosphere can only interact with the sediments. 

Fossils are remains of dead plants and animals. When plants and animals die, their bodies are buried inside the soil. the older the fossils, earlier they must have been buried inside. Year after, many bodies must have got deposited over them. So deeper the fossil layer, older it must have been.

Archeopteryx is a connecting link between reptiles and aves. It has large wings, and hollow bones like aves, and tail and legs like a dinosaur. Apart from these reptilian features, they also have abdominal ribs resembling reptiles. 

Its fossils (some teeth, skull cap and femur bone) were found in 1891 by a Dutch anatomist, Eugene Dubois on the bank of Solo river in Eastern Java.




 

ESA is a more precise technique than previously used techniques for the dating of fossils. It is based on the principle of resonance due to electrons and electron deficient centres produced as a result of emission by naturally occurring radioactive elements in a sample. DNA is the information macromolecule in a living system and can be extracted from fossils or other ancient samples. The sequence information in such a DNA can be compared against sequence information of DNA in other samples or living plants and animals, leading to valuable information about the evolution of plants and animals.

All these (coelacanth, limulus and sphenodon) are  representative of its own kind hence called living fossil.

Fossils are formed in a number of different ways, but most are formed when a plant or animal dies in a watery environment and is buried in mud and silt. Soft tissues quickly decompose leaving the hard bones or shells behind. Over time sediment builds over the top and hardens into rock.

Petrified fossils:- In geology, petrifaction or petrification is the process by which organic material becomes a fossil through the replacement of the original material and the filling of the original pore spaces with minerals.

Permineralization:- A process of fossilization in which mineral deposits form internal casts of organisms. Carried by water, these minerals fill the spaces within organic tissue.

Archaeospheroides is recognized as one of the oldest known microfossils, dating back to the Precambrian era, specifically associated with early blue-green algae.

The K-T boundary (Cretaceous-Tertiary boundary) marks the mass extinction event that occurred approximately 66 million years ago, separating the Cretaceous period from the Tertiary period.

The Himalayan and Alpine orogenies occurred primarily during the Cenozoic era, specifically starting in the early to middle parts of the era.

The earliest fossil evidence of land animals includes arthropods like centipedes and primitive spiders, which appeared during the Silurian or early Devonian periods.

Amber is fossilized tree resin that often traps insects and other small organisms, preserving them in a hardened, brownish substance.

Willard Libby is the scientist credited with the invention of radiocarbon dating in the late 1940s, for which he later won a Nobel Prize.

The oldest fossil evidence of land animals, such as early arthropods, dates back to approximately 440 million years ago, during the Silurian period.

Petrology is the branch of geology that studies the origin, composition, structure, and distribution of rocks.

Dating is the general term for the process of determining the age of geological materials, including fossils and rocks, using methods like radiometric or relative dating.

Ginkgo biloba is a living fossil because its ancestors are unchanged for the  last many hundred years, while its relatives disappeared.

From the given methods, the relatively most accurate method for dating of fossils is electron-spin resonance method. This method is based on the principle of measuring the number of charges occupied by the deep traps crystal band gap.

If fossil Y has vestigial structures that are homologous to functional structures in fossil X, it implies that X represents an earlier, more ancestral form, while Y represents a later form where the structure has become vestigial.

Fossils are the preserved remains of previously living organisms or their traces, dating from the distant past. Fossils document the existence of now-extinct species, showing that different organisms have lived on Earth during different periods of the planet's history. They can also help scientists reconstruct the evolutionary histories and ancestry of present-day species. For instance, some of the best-studied fossils are of the horse lineage. Using these fossils, scientists have been able to reconstruct a large, branching "family tree" for horses and their now-extinct relatives. 

Impressions are two-dimensional imprints of an organism that doesn't contain any organic material. An impression is a clue left of the organism's biological activity, they can be formed while the organism was moving or any other biological activity.
So the correct option is 'Impressions'.

Aegyptopithecus was an early primate that existed around 30 mya and it is widely believed to be ancestral to monkeys (cercopithecoids), as well as to humans and apes (hominoids). About 15 mya, primates called Dryopithecus and Ramapithecus were existing. They were hairy and walked like gorillas and chimpanzees. Ramapithecus was more man-like while Dryopithecus was more ape-like.