You can change the above code and rerun it. Ok, now let's do the same thing for a small Ant-Man. Of course, he is going to be smaller in his small form. This also means that each step will cover less distance. Suppose I shrink him by a scale factor of a. In order to make his run look like normal sized human, I would also have to decrease his velocity by the same factor a.
Oh, I would also make the spherical human smaller and the surface he is running on smaller by the same factor. Here is what that looks like. If everything is smaller, shouldn't it look the same? There is one thing that isn't smaller the gravitational field. This means that if tiny Ant-Man jumps with a lower speed, he won't go as high and he won't be off the ground for as long of a time. He is still taking hops, but the hops are super tiny and yes, this is a tiny man on a tiny surface. Everything is scaled down.
So, a tiny Ant-Man wouldn't run like a full sized human. It would look really weird. Maybe this is why humans and big animals like horses run and leave the ground when they move fast.
Insects just use multiple legs to move fast but don't get off the ground. That's just a guess. Oh, there is one way to make Ant-Man run in a normal looking fashion decrease the gravitational field g by the same scale factor. Try changing the code above to see if you can make it look better. Now let's look at a clip from the Ant-Man movie. What kind of vertical acceleration does tiny Ant-Man have in these moves?
The first step is to determine the actual size of the tiny Ant-Man. Fortunately, he appears next to an object of known size the hand gun held by the security guard. Using my lack of handgun knowledge really, I know nothing and my excellent Google-fu I am a black belt , I am fairly certain the weapon is a Glock From that, I can get a size estimate for Ant-Man. Some rights reserved. Homo floresiensis , laid out in approximate anatomical position.
All rights reserved. Initial descriptions emphasized the mix of ancestral traits that remained unchanged from more ancient species and derived traits that linked it with more recent ones. The skull resembles those belonging to extinct species of our own genus Homo Brown et al.
The skeleton, however, is considerably more primitive and in some respects aligns the LB1 specimen and the other Flores fossils with older and even more primitive species like those belonging to Australopithecus afarensis which includes "Lucy"; Tocheri et al.
Taken together, this is a puzzling pattern: a population that existed between 74 and 18 ka, with a skull that most closely resembles the much older Homo habilis or Homo erectus , and a skeleton that retains some features normally associated with australopith species at least 3 Ma. Presumably Homo floresiensis made the simple Oldowan-like tools the oldest and most primitive type known in the archaeological record found in the same layers as the skeletal remains at Liang Bua cave Moore and Brumm, These stone tools resemble those found elsewhere on the island at sites that are closer to a million years in age Brumm et al.
In addition to tools, there is also evidence in the form of cut marks on some Stegodon bones indicating that the hominins were butchering these animals Morwood et al. There are also some burnt bones and pebbles, but whether this was the result of intentional or accidental fire is still unknown Westaway et al. The phenomenon of island dwarfing has been documented for a number of other large-bodied mammals, including primates, mammoths, and deer.
There are also numerous instances of human populations becoming dwarfed, including on the islands of Southeast Asia. The impetus for island dwarfing is often linked to reduced availability of resources in the environment.
In either case, being small-bodied may be more advantageous on an island than on the mainland. Flores exists in a region known as Wallacea where there is a low level of migration from the Asian and Australasian faunas collections of animals to the east and west, respectively.
These islands appear to have been isolated by strong currents, even when sea levels were low. Along with the hominins, a few other large-bodied mammals have been documented in this region, including Stegodon , a type of extinct type of elephant, and komodo dragons.
Both of these species were found in deposits coeval with Homo floresiensis , however, their rarity is further confirmation that it was difficult for large terrestrial animals to reach islands in Wallacea. Interestingly, the particular subspecies of Stegodon found in the same layers of Liang Bua cave as Homo floresiensis , Stegodon florensis insularis , is itself a dwarfed form whose closest relative is the distinctly larger and geologically older Stegodon florensis florensis van den Bergh et al.
An argument against island dwarfing as an explanation for Homo floresiensis stems from the relationship between brain size and body size. LB1's endocranial volume , calculated from CT scans of the skull, is only cm 3 , close to a third of the average modern human value Falk et al.
This small brain size is difficult to explain based on typical patterns of island dwarfing assuming that the ancestor resembled a modern human or even Homo erectus Martin et al. This is because brain size typically "dwarfs" less than overall body size. For example, despite having bodies that are much smaller than their neighbors, modern human pygmies have brains which are only slightly smaller.
A second model advanced to explain the presence of the hominin fossils on the island of Flores in the Pleistocene states that this population was the offshoot of a more primitive, pre- erectus hominin species with a small body size and small brain. Evidence from the mandible and the rest of the skeleton supports this hypothesis Argue et al. The size and morphology of the teeth and mandible share more resemblances to Australopithecus and the earliest Homo species than to Homo erectus Brown and Maeda, In particular, the very short legs relative both to the arms and to the feet are a pattern seen in apes and australopiths rather than Homo erectus a good Homo habilis skeletal comparison has not yet been discovered.
LB1 was also disproportionately heavy for her height — a pattern closely approximated by the famous 3. Despite being only cm in height, LB1 is estimated to have weighed close to The carpal bones bones of the wrist in Homo floresiensis look more like those of chimpanzees than of modern humans Tocheri et al.
While the evolution of the wrist is not well documented in early members of the genus Homo e. Like the wrist, the foot morphology, although exhibiting some human-like traits including a non-grasping big toe , also retains several quite primitive features: a long forefoot with curved toes and the lack of a medial longitudinal arch Jungers et al.
The latter trait is indicated by the particular shape of the navicular bone, one of the bones close to the heel. This medial longitudinal arch is located on the inside aspect of the foot, forming the instep, and acts both as a shock absorber and a spring during walking. It seems likely that the relatively long foot and particular combination of traits present in the foot would have resulted in a slightly different walking gait than seen in modern humans.
This combination of traits in the skeleton appears to place the ancestry of the Homo floresiensis skeleton earlier than Homo erectus. One major challenge to the idea that Homo floresiensis has an ancestry deeper than Homo erectus is the absence of fossils of any such species in either island or mainland Southeast Asia. The hominin fossil record prior to Homo erectus is found only in Africa. A second complication is that the fossil record of postcranial anatomy for pre- erectus species of Homo is poor and their morphology is not as well documented as other species, so comparison with Homo floresiensis is limited.
As a result, it is not clear whether a species such as Homo habilis , which precedes Homo erectus geochronologically, is in fact a good model for the ancestor of Homo floresiensis. Homo taxa, illustrating some of the possible ancestors of Homo floresiensis : Asian Homo erectus or earlier Homo populations from Africa.
Figure 4: The LB1 cranium center compared to skulls of a modern human with endemic hypothyroidism left and a modern human showing microcephaly right. All photographs were scaled to the same maximum cranial length to emphasize shape differences among them. For example, the skull of the "cretin" on the left is much taller but shorter front-to-back than LB1. Despite the superficial similarities due to a small neurocranium relative to face in both LB1 and the microcephalic modern human, the midline profile of the neurocranium and the facial skeleton differ among them.
The photograph of the human with endemic hypothyroidism was mirrored for easier comparison with the other photographs. In addition to microcephaly, two other very different pathologies have been implicated: myxoedematous endemic hypothyroidism "cretinism"; Obendorf et al. The former is caused by a lack of iodine in the diet during both pre- and post-natal development Halpern et al.
The most notable symptoms of this disease include mental retardation and other neurological defects as well as short stature due to delayed skeletal maturity Boyages et al, The skull is often described as brachycephalic , and the sutures between individual bones of the skull frequently remain open even once brain growth has ended Koplik, , p.
However, the LB1 skull is not brachycephalic, and many of its cranial sutures are fully fused. In fact, the skulls of cretins are not particularly small, and their shape more closely resembles healthy humans than LB1 Baab, Some skulls of patients with congenital hypothyroidism exhibit an enlarged pituitary fossa.
This feature was initially attributed to the skull of LB1 Obendorf et al. While the skeletons of both human cretins and Homo floresiensis differ from that of healthy modern humans, they do not resemble one another. For example, the limb proportions of LB1 are not comparable to those of humans with cretinism Jungers et al. Laron Syndrome is characterized by insensitivity to growth hormones; although the body manufactures the correct growth hormones, the receptors in the body do not respond properly to them.
As in myexedemotous hypothyroidism, patients suffering from Laron Syndrome are of shorter than average stature. Although the original paper proposing that LB1 had Laron Syndrome found a number of similarities between the LB1 skeleton and individuals with Laron Syndrome Hershkovitz et al.
For example, with regards to the skull, patients with Laron Syndrome typically have a protruding forehead, underdeveloped facial bones such that the face looks small compared to the rest of the head, and a skull that is disproportionately wide across the parietal bones compared to the base of the skull. The LB1 skull shows the opposite pattern: the forehead slants backwards rather than protruding, the face is large relative to the rest of the skull, and it is wide at the base rather than the parietals Falk et al.
Rather, the various lines of evidence, from the simple stone tools, the Homo -like skull morphology, and the even more primitive skeletal anatomy, paint a more complicated evolutionary picture. The two most popular evolutionary hypotheses position Homo floresiensis as the dwarfed descendant of Homo erectus or descendant of an even more primitive species. If the former is correct, then Homo floresiensis certain skeletal traits reappeared in this lineage that were seen in earlier australopith species but lost prior to or at the origin of Homo erectus.
If the latter is true, then Homo floresiensis was descended from a species such as Homo habilis for which there is no evidence elsewhere in Asia. Only additional fossils or analyses will determine the evolutionary history of the "Hobbit" of Flores island. Australopithecus : An extinct hominin genus found only in Africa that preceded the genus Homo chronologically and contains several species spanning the time interval of 4.
Australopithecus afarensis : An extinct hominin species in the genus Australopithecus from East Africa in the time period 3. CT : Acronym for computed tomography which is an X-ray-based imaging technique used to see both the external and internal anatomy of structures such as skulls and teeth also known as CAT scanning in a clinical context.
Homo : An extinct hominin genus that includes our own species Homo sapiens among others. Members of this genus first appear in the fossil record about 2. The Liang Bua fossils have been assigned to this genus. Homo erectus : An extinct species of hominin that is in the same genus as modern humans Homo that was found in Africa, Eurasia and east Asia from 1.
Homo habilis : An extinct species of hominin that is in the same genus as modern humans Homo that was found in Africa from 2. Ma : Acronym referring to megaannum million years ; used to express ages in millions of years e. Oldowan : Oldest known stone tool technology most common in Africa 1. Less mass means fewer cells, which is what gives your body heat. So get ready to constantly run on a treadmill. Probably not. A study out of NYU looked into bioengineering and how it can affect climate change.
This includes things like food, clothing, even gas for the car. If people were smaller, things would just last longer. Experts say an impact like this would be enough to put a massive dent in climate change, maybe even reverse it. Researchers are looking into how we can make future generations smaller by genome editing. Although controversial, it might just be the way of the future. Babies might eventually be made in computers instead of in the womb.
Season 2 of "What If" takes you to an imaginary world where the laws of nature have been altered People on Earth talk a lot about colonizing Mars. But What If it had already happened and the first Imagine how fast we could exchange information if we could just transmit our thoughts directly to Some
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