Homo sapiens odio resistere conatur.

Because resistere normally takes the dative case in Latin, not the accusative.

So:

• odium = accusative or nominative form of hatred
• odio = dative singular, meaning to hatred or more naturally against hatred

English says resist hatred with a direct object, but Latin uses a different construction.

Yes, odio could be either dative singular or ablative singular in form. But in this sentence it is understood as dative, because resistere is the verb that governs it.

So the grammar points to:

• resistere alicui / alicui rei = to resist someone / something

Not every form has only one possible case, so learners often have to use syntax to decide.

Because it depends on conatur.

Conatur means tries or attempts, and after verbs like this Latin commonly uses an infinitive to show what someone tries to do.

So the structure is:

• conatur = he/she/it tries
• resistere = to resist

Together: tries to resist

Because conatur comes from a deponent verb.

A deponent verb:

• has passive-looking forms
• but an active meaning

The dictionary form is:

• conor, conari, conatus sum = to try

So:

• conatur looks passive
• but means he/she/it tries, not is tried

This is a very common thing in Latin and often confuses beginners.

Sapiens is a present participle used like an adjective.

It comes from sapio, sapere, meaning to be wise, to have sense, or to taste / perceive depending on context.

Here it agrees with homo and describes it:

• homo = human being / man
• sapiens = wise, sensible, knowing

So homo sapiens literally means a wise human being or a human being who is wise.

They are both nominative singular, because they form the subject of the sentence.

• homo = nominative singular
• sapiens = nominative singular agreeing with homo

Latin shows relationships mainly through endings, so agreement matters:

• same case
• same number
• same gender sense

That is how we know sapiens is modifying homo.

Not necessarily.

In ordinary Latin, homo sapiens can simply mean a wise human being. Modern readers may also recognize it as the scientific name Homo sapiens, but that scientific use is a later convention.

A learner should notice both possibilities:

• in classical-style Latin: probably just wise human
• in a modern scientific context: the human species

Context decides.

Because Latin has no articles like English the and a/an.

So homo sapiens could mean:

• a wise human being
• the wise human being
• sometimes just man or humankind, depending on context

Latin leaves that to context rather than marking it with a separate word.

No. Latin word order is much more flexible than English word order, because the endings already show the grammatical roles.

This sentence is arranged as:

• Homo sapiens = subject
• odio = object of resistere in the dative
• resistere = infinitive
• conatur = main verb

A Latin writer could rearrange the words for emphasis without changing the basic meaning, for example:

• Homo sapiens conatur odio resistere
• Odio homo sapiens resistere conatur

The chosen order may place a little emphasis on odio before the infinitive.

It can mean human being, not just adult male.

This is important because Latin distinguishes:

• homo = human being / person
• vir = man in the sense of an adult male, often with ideas of masculinity or courage

So in many contexts, homo sapiens is better understood as human being rather than specifically man.