Sea lions are seals
The topic should be self explanatory.
First round: Acceptance only.
Final round: Rebuttals only. No new arguments.
You flake, you lose.You troll, you lose.
I purposefully sustained from submitting an acceptance statement until now so that I may do research.
In light of my research, I would like my opponent to clarify at what level they are comparing seals to sea lions (as I hope this is not a debate about the semantics of their names). I will then provide my distinction and the Bop showing why that my distinction is more valid, should it differ from Pro's distinction.
I graciously accept this debate.
Re: Clarification as to "what level". I'm not quite sure what my opponent means when he asks about "what level". In any event, the first round is for acceptance only.
P1 - Any organism of the taxonomic family Phocidae or Otariidae is a seal.
P2 - All sea lions are organisms of the taxonomic family Otariidae.
C1 - Therefore, all sea lions are seals.
This argument is valid. If the premises are true, then the conclusion must be true.
* "P" is an abbreviation for "premise" and "C" is an abbreviation for "conclusion".
Support for P1 -
Support for P1 comes in the form of encyclopedic and dictionary entries for the word "seal". These references are reputable, sufficiently numerous, and are inclusive of the taxonomic families mentioned in P1. The family names have been emphasized.
Support for P2 -
Support for P2 comes in the form of encyclopedic and dictionary entries for the term "sea lion." These references are reputable, sufficiently numerous, and demonstrate that sea lion species are of the family Otariidae, which is also referred to as "eared seals."  "Otariidae" and/or "eared seal" have been emphasized.
I apologize to my opponent for the confusion, however, I was under the assumption that they would be aware that any conversation about the comparison of two organisms would involve some form of Taxonomy, which is known to have multiple levels of classification: Kingdom, Phylum/Division, Subphylum, Class, Order, Family, Genus, and finally Species . When one looks at taxonomy and all the classifications it begs the question: how do we determine what combines organisms together under a certain classification?
A. There are multiple ways to define and compare living organisms.
It would seem that we as Homo Sapiens have distinct need to classify things. Unfortunately, there is a plethora of techniques and approaches, that we can use to compare species. If you see a comparison, you should be asking if someone is using the Cladistic System (evolutionary similarities), Phenetic systems (physical attributes), or Genetic Systems . Then one must go further and ask if a person is considering sexual or environmental behavior, morphological function, DNA, RNA, etc . As we can see, the answers to these questions become complex and add to the difficulty of classification. Also, many names in the world are attributed to the first person that coined the term, however, that person may have been completely wrong in their logic, causing bias or misinterpretation. Thus, as stated before, it is important to know what level you are comparing two organisms and what methods they used to come to those conclusions.
B. Not all levels are equal and not all names are valid.
1. Species would be the best level for comparison as it is most specific.
As stated before determining the different groupings in a taxonomy can be difficult, even more so when you go higher in levels of classification (more general). When you start from the top you have many exceptions to rules, and as you get more specific you are then able to better distinguish and compare two different objects. When you try to compare things with umbrella terms, you start to get some challenges in your logic, for example; All squares are parallelograms. All squares and rectangles are quadrilaterals. However, one should not make the mistake to think then that all quadrilaterals are parallelograms, and not all parallelograms are squares . The same can be said for taxonomy levels, unless you are talking about species, you will have limitations to your use and claim that all of organism falls under a certain category and vice versa.
2. We are a world of misnomers and misconceptions.
Unfortunately in history, religion, politics and science many people fall into the fallacy of tradition (argumentum ad antiquitatem), where simply we are reluctant to amend something that has already been established, whether it be a law, ideology, or name. The downside of this, especially in science, if first person was wrong, then we all have it wrong, or more specifically we are using a misnomer . Briefly we have been exposed to many misconceptions based on the wrongful naming of things: spiders are not insects, star/jellyfish are not fish, Chinese checkers is not from china, global warming is...well, something, etc [6,7]. In the case of taxonomy, we are continuously making amendments to the grouping of organisms based on new techniques and findings that were not available to the people who coined the classification/name in the past.
C. Sea Lions and Seals have some interesting differences.
In the case of sea Lions and seals, it is important to investigate their similarities and differences that have placed them in the particular groupings they are today (although this is constantly fluid). Firstly, all seals and sea lions are Pinnipeds (fin-footed) marine animals . However, this also includes walruses and fur seals, which are an ambiguous group that causes much debate in their current placement. In fact “fur seals are named misleadingly because they are apart of the Otariidae family with sea lions,” and amongst sea lions and seals there are distinctions between diet, morphological function, and behavior . It is interesting consider that they would be called the same since these were the major ways of distinguishing animals apart before the mid-1900s.
Most studies now try to incorporate genetic studies as well as morphological (skull) studies to distinguish organisms in groups, which in turn comes up with more confusion and amendments to the lineage. In fact it is important to note that original classifications of these animals (sea lions) began in the 1800’s, and studies now show that fur seals and some other species of sea lions may have been placed under the wrong lines . In short, the best that we can say about differing organisms is that they may or may not similarities, depending on what study is being conducted. We cannot therefore claim umbrella names for divergent organisms, and must respect their differences.
My opponent argues many things. Yes, of course there are multiple ways to define and compare living organisms, but my opponent does not relate this to the central issue of this debate: Whether or not sea lions are seals.
My opponent argues that species would be the best level for comparison as it is most specific. However, this debate isn't about what level is the best for comparison. This debate is about whether or not sea lions are seals.
My opponent compares the categorization of species to categories of polygons. My opponent states that it would be a mistake to think "that all quadrilaterals are parallelograms." Perhaps my opponent intends to imply that, by the same token, it would be a mistake to think that all sea lions are seals. The implication, if it was intended, is incorrect. All sea lions indeed are seals as they are members of the family Otariidae. Sea lion is the sub-category; Seal is the encompassing category. With quadrilaterals are parallelograms, parallelogram is the sub-category, and quadrilateral is the encompassing category.
I also do not understand my opponent's notion that we must emphasize on the level of species. This doesn't really make sense to me. All sea lions are animals. "Animals" is a substantially broader term than "seals", and no reasonable person would dispute that all sea lions are animals.
I don't understand the relevance of my opponents discussion over misnomers and misconceptions because my opponent does not relate this discussion to the topic at hand.
My opponents debate section C - "Sea lions and seals have some interesting differences" - is full of inaccurate information. First, I must point out that saying that sea lions and seals have interesting differences would be similar to saying that canines and coyotes have interesting differences. This is because sea lions are simply a type of seal in the same way that coyotes are a type of canine.
Second, I must point out that walruses are not seals because walruses are not members of the family Otariidae nor Phocidae. Although both seals and walruses are pinnipeds, walruses are members of the family Odobenidae.  Pinnipedia is a suborder, not a family. 
Third, I must criticize Con's source 9, http://nmlc.org... . It's a blog post written by someone named Brie Myre, and it's a bad source that's full of misinformation. Ms. Myre appears to have written her blog post while operating under the mistaken belief that "seal" simply means members of the family Phocidae while "sea lion" simply means members of the family Otariidae. Ms. Myre was wrong. Ms. Myre's notions fly in the face of every dictionary definition and encyclopedic reference provided in round 1.
I don't know anything about Brie Myre, but I do know that this blog post is not as authoritative nor reputable as the sources I provided in round 1. I'll trust encyclopedias and dictionaries more than blog posts. My sources are more authoritative and reputable with regards to these particular assertions. Therefore, my sources should prevail.
Lastly, I offer some direct support for C3 - "Sea lions are seals" 
A. Pro’s use of dictionaries is insufficient.
My opponent is trying to persuade you that the definition of seals and sea lions are the sole evidence one should need to draw a conclusion that they are the same. When in fact I showed in my argument B2 that human beings have commonly been mistaken about our initial definitions of nature. Definitions, especially scientific, change readily. For example, initially people thought spiders were insects and Earth was the center of the universe. We even changed the definition of Pluto being the 9th planet of our solar system . As seen in this example and from my arguments A and B2, what we we initially observe may not be valid, and cannot be taken as absolute truth.
First I would like to point out that pro’s source #4 from Round 3 contradicts the statement “I must point out that walruses are not seals because walruses are not members of the family Otariidae nor Phocidae,” when in fact the source states that, “the seal family is a large one, including the huge walrus of the Arctic, the elephant seal, the sea-lion, the fur-seal and many other kinds which are just seals.” By following that logic then, seal should refer to walruses, sea-lions, and seals. Which means seals should be on a taxonomic level that includes all three organisms, and that level in taxonomy would be the sub-order Pinnipeds.
I would also like to briefly mention that pro’s source correlates with all the other definitions that pro has posted. If pro were to recant the validity of this source, then I would argue that this supports that the definitions posted about seals by pro are also outdated and invalid, since source #4 was written and carried out in 1902.
C. Pro states fallacious and/or invalid arguments/logic in their rebuttal.
1. “I don't understand the relevance of my opponents discussion over misnomers and misconceptions because my opponent does not relate this discussion to the topic at hand.”
Despite what pro may think, I relate my argument B2 with the fact that older definitions can and have been known to be misnomers or misunderstandings. I also state in that an argument which simply states ambiguous nomenclature as pure definitions based on tradition, even if the name is a misnomer or misunderstanding, is an argumentum ad antiquitatem. This supports my argument that we cannot solely base our distinctions of two organisms based on their given definitions, for those definitions may be bias or misleading, and therefore require investigation on how they were obtained.
2. Pro poorly criticizes Argument C.
a. Pro’s criticism of source #9, RD 2
Briefly, Pro disregards that my source is a blog post from the site of a respected institution, the National Marine Life Center, which is dedicated to the education of marine animals as well as the rehabilitation of endangered animals, while at the same time conducting research and publishing respectable works [3, 4, 5]. Secondly Brie Myer is, at the least, a biology graduate student (unknown about her degree since she wrote her blog info in 2009) who did an internship at the National Marine Life Center, and submitted that particular blog I sourced while conducting research with other scientist [6, 7, 8]. I will let the reviewing members determine what is reputable or not.
b. Pro’s attack of Brie is biased.
Pro’s sole criticism of Brie’s blog is that she is wrong because she is “operating under the mistaken belief, that ‘seal’ simply means members of the family Phocidae while "sea lion" simply means members of the family Otariidae.” Yet pro fails to provide evidence showing why her assertion, and subsequently mine, is wrong other than we should take the population definition as absolute (argumentum ad populum). Furthermore, as pro has not shown how Myre is not a reasonable person, it weakens his argument and shows that there are people that do not agree with pro’s given definitions. Pro also fails to provide evidence why the other facts about the differences between seal and sea lion mating, eating, and morphology are absurd (argumentum ad lapidem).
c. Pro ignores other sources from Argument C.
Pro was hasty to state that Argument C fell apart due to the criticism of source 9 when in fact pro failed to mention sources 8 and 10 which support that:
3. We must understand taxonomic levels in order to compare if sea lions are seals.
a. Pro states they do not understand the need for comparison from species level of taxonomy.
If I confused my opponent I am sorry that was not my intention. I am simply asserting that if one is to compare organisms, they must consider species first then genus and slowly get more general. Simply focusing on one level in taxonomy that is broad is not sufficient. As stated before, the term “seals” seems to have been misused and should either relate to phocids only (based on contradictions stated above) or pinnipeds, the latter of which pro has already claimed is not true. Also I believe pro is misunderstanding what it means to be related to a family versus what makes a distinct species. For example, dogs and wolves are related to each other by the family canidae but there is also a clear distinction between a wolf and what is a dog. In light of this, dogs are also related to pinnipeds under the canidae superfamily (which include bears, weasels, skunks, and raccoons too), but one would not call a dog a seal either . If you were to however start at the species level, you can then keep comparing what makes animals different.
b. Being related does not mean you are the same.
While Pro would have you believe that being related in a family is sufficient enough to claim organisms are the same, this simply is not true, as there is a ~1% genetic difference between chimpanzees and human beings, but we define ourselves completely different and do not refer to ourselves as monkeys/apes [10, 11]. Taxonomy only tells us how we are likely related towards each other.
In light of this, studies have shown that sea lion species and seal species differ from each other genetically by 8% or more and range from 10-20% difference between other species including humans [12, 13]. Thus seals and sea lions differ from one another significantly in genetics, morphology, environmental niches, and behavior.
Sources: 11-13 in comments.
Con states that my "use of dictionaries is insufficient." He is mistaken. Dictionaries and encyclopedias are sufficient to establish that sea lions are seals. This debate is about definitions. Encyclopedias and dictionaries are perhaps the most authoritative source for definitions. That's what they're for.
Con's comparison of this debate to insects and spiders is not relevant. The same could be said of his comparison of this debate to the debate over whether or not Pluto is a planet. This debate is not about those things. This debate is about sea lions and seals.
Con claims that I made "a major contradiction." This is false, and Con is nitpicking. One of my sources states that walruses are seals, while I stated that walruses are not seals. The source contradicted my claim. I did not contradict myself. Furthermore, the "contradiction" in question is not relevant to this debate. This debate is about whether or not sea lions are seals. This debate is not about whether or not walruses are seals.
I stand by my criticism of Brie Myer's blog post. That blog post is contradicted by more authoritative sources - Encyclopedias and dictionaries. The more authoritative sources should prevail.
Con claims that his other sources, 8 and 10 from the prior round, support his assertions. However, Con merely links rather large articles and does not quote them. It's unreasonable to expect me or the voters to dig through these sources. Con's source 10 - http://www.researchgate.net... - is 101 pages long. Con's source 8 - http://what-when-how.com... - isn't too long, but I simply don't see what language is supposedly supporting Con's assertions in that article. Furthermore, Con's source 8 is a blog post. It is not as authoritative nor reputable as Britannica or Oxford.
Con then argues, for some reason, that the statement "Sea lions are seals" claims that sea lions and seals are the same thing. That is not true. All sea lions are seals, but not all seals are sea lions. The reason is similar to Con's discussion over polygons - All squares are quadrilaterals but not all quadrilaterals are squares.
I only agree with my opponent on one aspect, that this debate is, in the grand scheme, about the definition of sea lions and seals, however, what pro seems to misunderstand is that the very definition itself is under criticism. In this debate, pro has made substantial logical fallacies without supporting evidence or facts, as well as contradictions to his own premises.
A. Pro makes appeal to authority fallacy.
Pro has significantly lacked counter-arguments other than to say that dictionaries are the most reputable sources one can use for definitions. However, as stated before, definitions can and have been shown in history to be wrong or misunderstandings of what actually is occurring and therefore must be changed. Dictionaries only report definitions that are most popular by majority of population. The majority, however, does not mean that the ideal is right, as was seen when everyone at one point thought the earth was the center of the universe.
Thus, when we have a debate about the definition, that means that the dictionaries are at question as well and require supporting evidence to show why that definition is valid, which pro does not provide. Pro’s sole dismissal of my evidence and ideals, showing the difference between seals and sea lions, is based on the appeal to authority . Pro thus relies on circular reasoning to attack my assertions. In pro’s logic: sea lions are seals because of his given definitions, and the given definitions are valid because sea lions are seals.
B. Pro fails to address arguments showing differences.
Pro tires to persuade the audience that the supporting evidence for my arguments are invalid (as seen above) or are too lengthy to read. While pro argues that quotation is needed for better detail of the source, failure to go through an opponent's source because of its length is a problem for Pro, not mine. On the other hand, pro has only sent dictionary definitions of seals without any scientific studies, taxonomic studies, biological or morphological articles to support these claims. In addition, pro has sourced incomplete books as reference so that I cannot completely check and see if anything is out of context. I argue that in this debate Pro’s arguments are on the same level of using the bible for debate, where every word and definition is taken as absolute fact and somehow that removes the burden for Pro to show any other correlating or substantial evidence.
C. Pro’s conclusion about dismissing my arguments is misplaced.
While pro quickly dismisses arguments, evidence, and testimonies from my various sources, pro does not realize that, if anything, I have shown that there is not a convergence in the definition of seals, which would validate my claim that there needs to be an in-depth investigation on the placement and definition of seals and sea lions. Furthermore this weakens pro’s assertion that reasonable people would come to the same conclusion and therefore leads to the conclusion that pro’s definitions are not fact, for if they were, there would not be such a great divergence.
D. Pro’s contradiction still holds and is significant in this debate.
Pro tries to convince the audience that the contradiction from above was not significant and is nitpicking. However I must address some key points to why the contradiction holds and why it significantly weakens pro’s argument.
1. Pro’s sources make a point to distinguish between sea lions, fur seals, seals, and walruses. Thus, the definitions do not make a set point with where seals end and what really counts as seals. This is considerable if pro’s premise is to distinguish between some groups of the pinnipeds but not the others.
2. Pro’s sources are very general to a point where they are not useful pieces of evidence. Some of pro’s sources even go to say that seals are “mammals that mainly live in cold regions.” Clearly that could also include walruses, sea lions, but also dolphins, whales, etc. Which parts of those definitions are we suppose to use if they all are different? I answer that we should not be picking and choosing if the definitions are valid.
3. If Pro is going to state that dictionaries and the other sources are the most authoritative and reputable then it weakens pro’s argument when pro later picks and chooses which of their own sources we are suppose to take to heart.
If anything the source showing the contradiction further shows that there is not an absolute definition to the term seal and supports my assertions that older definitions are misunderstanding the distinction between seals and sea lions.
I have shown that definitions of an organism are based on taxonomic studies using morphology, physiology, behavior, and genetics to help relate species to other species. However, as many definitions of the natural world were made a long ago in history, the definitions in dictionaries may be misleading to the natural world and therefore invalid. We must then look into supporting evidence as to what makes animals under a nomenclature the same or different. I have shown that seals and sea lions have significant differences to be considered two separate entities. Pro has failed to effectively provide supporting or counter evidence other than dictionaries, since pro’s appeals to authority are suppose to be absolute. On the other hand, I have shown pro has committed contradictions, generalizations, as well as illogical fallacies, and subsequently weakened pro’s premises. Therefore, I conclude that pro’s conclusion is also invalid.